Add workflow to upgrade Maven Wrapper

This GHA workflow checks for new Maven Warper scripts and upgrades Maven to
latest GA release (currently 3.x).
It runs once a week and creates a PR for possible changes.

Signed-off-by: Holger Friedrich <mail@holger-friedrich.de>

Author: holgerfriedrich

.github/workflows/update-maven.yml

@@ -0,0 +1,54 @@
+name: Update Maven Wrapper
+
+on:
+  schedule:
+    - cron: '0 19 * * 5'
+  workflow_dispatch:
+
+jobs:
+  update:
+    permissions:
+      contents: write
+      pull-requests: write
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: actions/setup-java@v4
+        with:
+          java-version: '21'
+          distribution: 'temurin'
+
+      - name: Get latest Maven version
+        # This fetches latest Maven releas from maven.org - not the download page; it might be delayed a few days after releases.
+        # Note that the "gav" at the end of the URL ensures we use only generally available version. As of now, this is 3.x.
+        id: maven
+        run: |
+          LATEST=$(curl -s "https://search.maven.org/solrsearch/select?q=g:org.apache.maven+a:apache-maven&rows=1&wt=json&core=gav" \
+            | jq -r '[.response.docs[].v | select(test("^3\\.\\d+\\.\\d+$"))] | first')
+          echo "version=$LATEST" >> $GITHUB_OUTPUT
+
+      - name: Update wrapper
+        # Update Maven wrapper scripts AND maven-wrapper.properties.
+        # Note that this removes the SHA from properties file.
+        run: ./mvnw wrapper:wrapper -Dmaven=${{ steps.maven.outputs.version }}
+
+      - name: Patch SHA512 into wrapper properties
+        # Add the SHA to properties file.
+        # We might need the -L for curl, as after a new release all old SHA files will move to .
+        run: |
+          VERSION=${{ steps.maven.outputs.version }}
+          MAJOR=$(echo "$VERSION" | cut -d. -f1)
+          SHA=$(curl -sL "https://downloads.apache.org/maven/maven-${MAJOR}/${VERSION}/binaries/apache-maven-${VERSION}-bin.zip.sha512")
+          PROPS=".mvn/wrapper/maven-wrapper.properties"
+          sed -i '/^distributionSha512Sum=/d' "$PROPS"
+          echo "distributionSha512Sum=${SHA}" >> "$PROPS"
+
+      - name: Open PR if changed
+        uses: peter-evans/create-pull-request@c0f553fe549906ede9cf27b5156039d195d2ece0 # 8.1.0
+        with:
+          commit-message: "Update maven wrapper to ${{ steps.maven.outputs.version }}"
+          title: "Update Maven Wrapper to ${{ steps.maven.outputs.version }}"
+          branch: gha/update-maven-wrapper
+          delete-branch: true
+          labels: infrastructure