chore(ci): remove unused files and actions

Changelog is not really useful as we generated the changelog during release in Github releases

Closes #5813

.github/actions/automatic-updates/action.yml

@@ -50,12 +50,6 @@ runs:
         distribution: ${{ inputs.javaDistribution }}
         java-version: ${{ inputs.javaVersion }}
 
-    - name: Generate changelog
-      uses: ./.github/actions/changelog
-      with:
-        token: ${{ inputs.secretGithubToken }}
-        release_branch: ${{ inputs.branch-ref }}
-
     # Autogenerated resources
     - name: Run project refresh actions
       shell: bash
@@ -97,7 +91,7 @@ runs:
       run: |
         git config --local user.email "$CI_EMAIL"
         git config --local user.name "$CI_USER"
-        git add README.adoc CHANGELOG.md && git commit -m 'chore: nightly automatic updates' || echo "No nightly automatic updates changes to commit"
+        git commit -am 'chore: nightly automatic updates' || echo "No nightly automatic updates changes to commit"
         git push "https://$CI_USER:$CI_TOKEN@github.com/$GITHUB_REPOSITORY.git" HEAD:${{ inputs.branch-ref }} || echo "No nightly automatic updates changes to push"
 
     # Give it a rest to avoid hitting Github API rate limit

.gitmodules

@@ -1,6 +1,3 @@
-[submodule ".github/actions/changelog"]
-	path = .github/actions/changelog
-	url = https://github.com/CharMixer/auto-changelog-action
 [submodule ".github/actions/gh-go-mod-generate-sbom"]
 	path = .github/actions/gh-go-mod-generate-sbom
 	url = https://github.com/CycloneDX/gh-gomod-generate-sbom/