Bump doctrine/.github from 5.3.0 to 6.0.0

Bumps [doctrine/.github](https://github.com/doctrine/.github) from 5.3.0 to 6.0.0.
- [Release notes](https://github.com/doctrine/.github/releases)
- [Commits](doctrine/.github@5.3.0...6.0.0)

---
updated-dependencies:
- dependency-name: doctrine/.github
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

.github/workflows/coding-standards.yml

@@ -11,4 +11,4 @@ on:
 jobs:
   coding-standards:
     name: "Coding Standards"
-    uses: "doctrine/.github/.github/workflows/coding-standards.yml@5.3.0"
+    uses: "doctrine/.github/.github/workflows/coding-standards.yml@6.0.0"

.github/workflows/release-on-milestone-closed.yml

@@ -8,7 +8,7 @@ on:
 jobs:
   release:
     name: "Git tag, release & create merge-up PR"
-    uses: "doctrine/.github/.github/workflows/release-on-milestone-closed.yml@5.3.0"
+    uses: "doctrine/.github/.github/workflows/release-on-milestone-closed.yml@6.0.0"
     secrets:
       GIT_AUTHOR_EMAIL: ${{ secrets.GIT_AUTHOR_EMAIL }}
       GIT_AUTHOR_NAME: ${{ secrets.GIT_AUTHOR_NAME }}