fix(argoconfig): Remove empty syncPolicy from application template

[maxthier]

Description

This PR removes the empty syncPolicy from the application template. This change is needed because when you don't specify a syncPolicy in one of the helm-charts which use argoconfig, it will put just the empty syncPolicy in it. It seems like argoCD removes the empty value, which can be seen here:

time="2024-01-11T17:04:51Z" level=info msg="Refreshing app status (comparison expired, requesting refresh. reconciledAt: 2024-01-11 16:58:51 +0000 UTC, expiry: 3m0s), level (2)" application=infra-argocd/app-stackrox-secured-cluster-services
time="2024-01-11T17:04:51Z" level=info msg="Comparing app state (cluster: https://kubernetes.default.svc, namespace: infra-stackrox)" application=infra-argocd/app-stackrox-secured-cluster-services
time="2024-01-11T17:04:51Z" level=info msg="getRepoObjs stats" application=infra-argocd/app-stackrox-secured-cluster-services build_options_ms=0 helm_ms=13 plugins_ms=0 repo_ms=0 time_ms=408 unmarshal_ms=395 version_ms=0
time="2024-01-11T17:04:52Z" level=info msg="Normalized app spec: {\"spec\":{\"syncPolicy\":null}}" application=infra-argocd/app-stackrox-secured-cluster-services
time="2024-01-11T17:04:53Z" level=info msg="Update successful" application=infra-argocd/app-stackrox-secured-cluster-services
time="2024-01-11T17:04:53Z" level=info msg="Reconciliation completed" application=infra-argocd/app-stackrox-secured-cluster-services dedup_ms=0 dest-name= dest-namespace=infra-stackrox dest-server="https://kubernetes.default.svc" diff_ms=793 fields.level=2 git_ms=408 health_ms=1 live_ms=300 patch_ms=202 setop_ms=0 settings_ms=0 sync_ms=0 time_ms=2794

This leads to a diff between the desired and live manifest.
After this change the helm-charts which depend on this also have to update their dependency to fix the issue.

Issues

Checklist

• This PR contains a description of the changes I'm making
• I updated the version in Chart.yaml
• I updated the changelog with an artifacthub.io/changes annotation in Chart.yaml, check the example in the documentation.
• I updated applicable README.md files using pre-commit run
• I documented any high-level concepts I'm introducing in docs/
• CI is currently green and this is ready for review
• I am ready to test changes after they are applied and released

[eyenx]

LGTM