Make Update target a shared workflow and move configuration into pom

The workflow to update the target file is quite convenient and proven to
work well.

This now moves the configuration into the pom and makes the workflow a
shared one so it can be used in other projects easily.

.github/workflows/README.MD

@@ -40,4 +40,36 @@ It checks all artifacts that match the provided range and suggest a lower bound
 
 Workflow that could be used as a timed action to check if any automatic code cleanup can be performed.
 Actions to perform must be defined in the configuration of the [quickfix-and-cleanup-mojo](https://github.com/eclipse-tycho/tycho/blob/main/RELEASE_NOTES.md#new-quickfix-and-cleanup-mojo)
-that is called by this action. For this purpose it uses the follwoing execution ids `cleanups` and `quickfixes`
+that is called by this action. For this purpose it uses the follwoing execution ids `cleanups` and `quickfixes`
+
+## updateTarget.yml
+
+A Workflow that automatically checks a target file for updates of its dependencies.
+
+It has the follwoing inputs:
+- author - desired commit author / email 
+- token - token to use to create the PR while this action can work without it, it is recommended to use a PAT if used as a timed action because otherwhise PR checks can't run, see [here](https://github.com/marketplace/actions/create-pull-request#token) for details.
+- path - path to a project that contains the target to update
+
+and exspect that the pom configures an execution named `update-target` for its configuration, or otherwhise is running with the defaults. 
+An example might look like this:
+
+```
+<plugin>
+  <groupId>org.eclipse.tycho.extras</groupId>
+  <artifactId>tycho-version-bump-plugin</artifactId>
+  <version>${tycho.version}</version>
+  <executions>
+    <execution>
+        <id>update-target</id>
+        <configuration>
+            <allowMajorUpdates>false</allowMajorUpdates>
+            <updateSiteDiscovery>parent</updateSiteDiscovery>
+            <mavenRulesUri>${project.basedir}/update-rules.xml</mavenRulesUri>
+        </configuration>
+    </execution>
+  </executions>
+</plugin>
+```
+
+See the [tycho-version-bump:update-target](https://tycho.eclipseprojects.io/doc/latest/tycho-extras/tycho-version-bump-plugin/update-target-mojo.html) for further details.

.github/workflows/callUpdateTarget.yml

@@ -0,0 +1,25 @@
+name: Check for Target Platform updates
+
+concurrency: 
+    group: ${{ github.workflow }}-${{ github.ref }}
+    cancel-in-progress: true
+
+on:
+  workflow_dispatch:
+  schedule:
+    - cron:  '0 */2 * * *'
+  push:
+    branches:
+      - master
+    paths:
+      - '**.target'
+
+
+jobs:
+  update:
+    uses: eclipse-platform/eclipse.platform.releng.aggregator/.github/workflows/updateTarget.yml@master
+    with:
+      author: Eclipse Releng Bot <[email protected]>
+      path: 'eclipse.platform.releng.prereqs.sdk'
+    secrets:
+      token: ${{ secrets.RELENG_BOT_PAT }}

.github/workflows/updateTarget.yml

@@ -5,14 +5,22 @@ concurrency:
     cancel-in-progress: true
 
 on:
-  workflow_dispatch:
-  schedule:
-    - cron:  '0 0 * * *'
-  push:
-    branches:
-      - master
-    paths:
-      - '**.target'
+  workflow_call:
+    inputs:
+      author:
+        description: Defines the committer / author that should be used for the commit
+        required: false
+        type: string
+        default: ${{ github.actor }} <${{ github.actor_id }}+${{ github.actor }}@users.noreply.github.com>
+      path:
+        description: Defines the committer / author that should be used for the commit
+        required: true
+        type: string
+    secrets:
+      token:
+        description: Personal Access Token to use for creating pull-requests
+        required: false
+        default: ${{ secrets.GITHUB_TOKEN }}
 jobs:
   update:
     runs-on: ubuntu-latest
@@ -33,11 +41,8 @@ jobs:
         cache: maven
     - name: Update Target Platform
       run: >-
-          mvn -ntp -f eclipse.platform.releng.prereqs.sdk 
-          org.eclipse.tycho.extras:tycho-version-bump-plugin:4.0.9:update-target
-          -DallowMajorUpdates=false
-          -Ddiscovery=parent
-          -Dmaven.version.rules=update-rules.xml
+          mvn -ntp -f ${{ inputs.path }} 
+          tycho-version-bump:update-target@update-target
     - name: Create Pull Request
       uses: peter-evans/create-pull-request@5e914681df9dc83aa4e4905692ca88beb2f9e91f # v7.0.5
       with:
@@ -47,8 +52,8 @@ jobs:
         body: Please review the changes and merge if appropriate, or cherry pick individual updates.
         delete-branch: true
         draft: false
-        token: ${{ secrets.RELENG_BOT_PAT }}
-        committer: Eclipse Releng Bot <[email protected]>
-        author: Eclipse Releng Bot <[email protected]>
+        token: ${{ secrets.token }}
+        committer: ${{ inputs.author }}
+        author: ${{ inputs.author }}
         add-paths: |
             **/*.target

eclipse-platform-parent/pom.xml

@@ -532,6 +532,21 @@
           <artifactId>tycho-versions-plugin</artifactId>
           <version>${tycho.version}</version>
         </plugin>
+        <plugin>
+          <groupId>org.eclipse.tycho.extras</groupId>
+          <artifactId>tycho-version-bump-plugin</artifactId>
+          <version>${tycho.version}</version>
+          <executions>
+            <execution>
+                <id>update-target</id>
+                <configuration>
+                    <allowMajorUpdates>false</allowMajorUpdates>
+                    <updateSiteDiscovery>parent</updateSiteDiscovery>
+                    <mavenRulesUri>${project.basedir}/update-rules.xml</mavenRulesUri>
+                </configuration>
+            </execution>
+          </executions>
+        </plugin>
         <plugin>
           <groupId>org.eclipse.tycho</groupId>
           <artifactId>tycho-cleancode-plugin</artifactId>