Bump actions/cache from 3 to 4 (#354)

Bumps [actions/cache](https://github.com/actions/cache) from 3 to 4.
- [Release notes](https://github.com/actions/cache/releases)
- [Changelog](https://github.com/actions/cache/blob/main/RELEASES.md)
- [Commits](actions/cache@v3...v4)

---
updated-dependencies:
- dependency-name: actions/cache
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

.github/workflows/ci.yaml

@@ -43,7 +43,7 @@ jobs:
         env:
           ImageOS: ubuntu20
       - name: Retrieve Cached Dependencies
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         id: mix-cache
         with:
           path: |
@@ -98,7 +98,7 @@ jobs:
           ImageOS: ubuntu20
 
       - name: Retrieve Elixir Cached Dependencies
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         id: mix-cache
         with:
           path: |
@@ -162,7 +162,7 @@ jobs:
           elixir-version: ${{ matrix.elixir }}
           otp-version: ${{ matrix.otp }}
       - name: Retrieve Cached Dependencies
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         id: mix-cache
         with:
           path: |
@@ -198,7 +198,7 @@ jobs:
         with:
           ref: main
       - name: Retrieve Cached Dependencies - main branch
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         id: mix-cache-main
         if: github.ref_name != 'main'
         with:
@@ -239,7 +239,7 @@ jobs:
       - name: Checkout current branch
         uses: actions/checkout@v4
       - name: Retrieve Cached Dependencies - current branch
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         id: mix-cache-current
         with:
           path: |
@@ -256,7 +256,7 @@ jobs:
         with:
           ref: main
       - name: Retrieve Cached Dependencies - main branch
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         id: mix-cache-main
         with:
           path: |
@@ -381,7 +381,7 @@ jobs:
           elixir-version: ${{ env.ELIXIR_VERSION }}
           otp-version: ${{ env.OTP_VERSION }}
       - name: Retrieve Cached Dependencies
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         id: mix-cache
         with:
           path: |