build: update CI workflows to use Java 21

The project source/target compatibility was changed to Java 21 but CI
workflows still used Java 17, causing compilation failures.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: a-oren

.github/workflows/IJ-latest.yml

@@ -15,10 +15,10 @@ jobs:
 
     steps:
       - uses: actions/checkout@v4
-      - name: Set up JDK 17
+      - name: Set up JDK 21
         uses: actions/setup-java@v3
         with:
-          java-version: 17
+          java-version: 21
           distribution: 'temurin'
           cache: 'gradle'
       - name: Grant execute permission for gradlew

.github/workflows/IJ.yml

@@ -16,10 +16,10 @@ jobs:
     steps:
       - name: Checkout Code
         uses: actions/checkout@v4
-      - name: Set up JDK 17
+      - name: Set up JDK 21
         uses: actions/setup-java@v3
         with:
-          java-version: 17
+          java-version: 21
           distribution: 'temurin'
           cache: 'gradle'
       - name: Grant execute permission for gradlew

.github/workflows/ci.yml

@@ -15,10 +15,10 @@ jobs:
 
     steps:
     - uses: actions/checkout@v2
-    - name: Set up JDK 17
+    - name: Set up JDK 21
       uses: actions/setup-java@v3
       with:
-        java-version: 17
+        java-version: 21
         distribution: 'temurin'
         cache: 'gradle'
     - name: Grant execute permission for gradlew
@@ -34,10 +34,10 @@ jobs:
 
     steps:
     - uses: actions/checkout@v2
-    - name: Set up JDK 17
+    - name: Set up JDK 21
       uses: actions/setup-java@v3
       with:
-        java-version: 17
+        java-version: 21
         distribution: 'temurin'
         cache: 'gradle'
     - name: Grant execute permission for gradlew
@@ -53,10 +53,10 @@ jobs:
 
     steps:
     - uses: actions/checkout@v2
-    - name: Set up JDK 17
+    - name: Set up JDK 21
       uses: actions/setup-java@v3
       with:
-        java-version: 17
+        java-version: 21
         distribution: 'temurin'
         cache: 'gradle'
     - name: Grant execute permission for gradlew

.github/workflows/publish-marketplace.yml

@@ -24,10 +24,10 @@ jobs:
       - name: Checkout repository
         uses: actions/checkout@v4
 
-      - name: Set up JDK 17
+      - name: Set up JDK 21
         uses: actions/setup-java@v4
         with:
-          java-version: 17
+          java-version: 21
           distribution: 'temurin'
           cache: 'gradle'
 

.github/workflows/release.yml

@@ -8,10 +8,10 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v2
-      - name: Set up JDK 17
+      - name: Set up JDK 21
         uses: actions/setup-java@v3
         with:
-          java-version: 17
+          java-version: 21
           distribution: 'temurin'
           cache: 'gradle'
       - name: Grant execute permission for gradlew

.github/workflows/stage.yml

@@ -17,10 +17,10 @@ jobs:
       - name: Checkout sources
         uses: actions/checkout@v4
 
-      - name: Install Java 17
+      - name: Install Java 21
         uses: actions/setup-java@v3
         with:
-          java-version: 17
+          java-version: 21
           distribution: 'oracle'
           cache: 'gradle'