ci: optimize test workflow by separating runtimehints from engine matrix

This change improves the CI workflow's efficiency by splitting the testing into specialized jobs:
1. Runtime hints tests now only permutate on JDK versions, not Redis/Valkey engine types or versions, since these tests validate Java runtime behavior for native image compilation rather than Redis-specific functionality.
2. Removed unnecessary Redis/Valkey installation steps and server version parameter from runtime hints tests.
3. Baseline tests continue to run the full matrix permutation across JDK versions and Redis/Valkey engine combinations.

This approach significantly reduces CI execution time and resource usage while maintaining complete test coverage, following the pattern established in the Jenkins pipeline which also runs runtime hints tests with a single Redis version.

Signed-off-by: ikolomi <ikolomin@amazon.com>

Author: ikolomi

.github/workflows/ci.yml

@@ -13,16 +13,17 @@ on:
   workflow_dispatch:
 
 jobs:
-  generate-tests-matrix:
+  generate-test-matrices:
     runs-on: ubuntu-latest
     outputs:
-      matrix: ${{ steps.set-tests-matrix.outputs.matrix }}
+      full-matrix: ${{ steps.set-full-matrix.outputs.full-matrix }}
+      jdk-matrix: ${{ steps.set-jdk-matrix.outputs.jdk-matrix }}
     steps:
       - name: Checkout code
         uses: actions/checkout@v4
 
-      - name: Read and expand tests-matrix.json
-        id: set-tests-matrix
+      - name: Read and expand full tests-matrix.json
+        id: set-full-matrix
         run: |
           jq -n '
             [inputs[] |
@@ -40,17 +41,25 @@ jobs:
               )
             ]
           ' .github/workflows/tests-matrix.json > tests-matrix-expanded.json
-          echo "matrix=$(cat tests-matrix-expanded.json | jq -c .)" >> $GITHUB_OUTPUT
+          echo "full-matrix=$(cat tests-matrix-expanded.json | jq -c .)" >> $GITHUB_OUTPUT
 
-  ci-tests:
-    needs: generate-tests-matrix
+      - name: Extract JDK versions only
+        id: set-jdk-matrix
+        run: |
+          jq -n '
+            [inputs[].["openjdk-versions"][] | { jdk: . }]
+          ' .github/workflows/tests-matrix.json > jdk-matrix-expanded.json
+          echo "jdk-matrix=$(cat jdk-matrix-expanded.json | jq -c .)" >> $GITHUB_OUTPUT
+
+  ci-baseline-tests:
+    needs: generate-test-matrices
     runs-on: ubuntu-latest
     timeout-minutes: 30
     strategy:
       fail-fast: false
       matrix:
-        include: ${{ fromJson(needs.generate-tests-matrix.outputs.matrix) }}
-    name: Test JDK ${{ matrix.jdk }} with ${{ matrix.engine }} ${{ matrix.version }}
+        include: ${{ fromJson(needs.generate-test-matrices.outputs.full-matrix) }}
+    name: Baseline test with JDK ${{ matrix.jdk }} and ${{ matrix.engine }} ${{ matrix.version }}
 
     steps:
       - name: Checkout
@@ -90,12 +99,50 @@ jobs:
             -Dredis.server.version=${{ matrix.redis-version || matrix.valkey-version }} \
             -U -B
 
-      - name: Test baseline
+  ci-runtimehints-tests:
+    needs: generate-test-matrices
+    runs-on: ubuntu-latest
+    timeout-minutes: 30
+    strategy:
+      fail-fast: false
+      matrix:
+        include: ${{ fromJson(needs.generate-test-matrices.outputs.jdk-matrix) }}
+    name: Test runtime hints with JDK ${{ matrix.jdk }}
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Set up JDK
+        uses: actions/setup-java@v4
+        with:
+          java-version: ${{ matrix.jdk }}
+          distribution: "temurin"
+
+      - name: Cache Maven dependencies
+        uses: actions/cache@v4
+        with:
+          path: ~/.m2/repository
+          key: ${{ runner.os }}-maven-${{ hashFiles('**/pom.xml') }}
+          restore-keys: |
+            ${{ runner.os }}-maven-
+            
+      # Runtime hints tests still need a Redis instance, but can use a single version
+      - name: Install Redis
+        uses: ./.github/workflows/actions/install-engine
+        with:
+          engine-type: "valkey"
+          engine-tag: "8.0.3"  # Use oldest valkey version for runtime hints tests
+
+      - name: Start Valkey
+        run: |
+          make start
+
+      - name: Test runtimehints
         run: |
           ./mvnw -s settings.xml \
             -Ddevelocity.storage.directory=$HOME/.develocity-root \
             -Dmaven.repo.local=$HOME/.m2/spring-data-redis \
             test -Pruntimehints \
             -DrunLongTests=false \
-            -Dredis.server.version=${{ matrix.redis-version || matrix.valkey-version }} \
             -U -B