Add Gradle daemon JVM properties and sync Java version

.github/workflows/build-kdoc.yml

@@ -18,7 +18,7 @@ jobs:
       - uses: actions/setup-java@v5
         with:
           distribution: temurin
-          java-version: 21
+          java-version: 21   # keep in sync with gradle/gradle-daemon-jvm.properties
           cache: gradle
       - uses: gradle/actions/setup-gradle@v6
 

.github/workflows/test-dev.yml

@@ -13,7 +13,7 @@ jobs:
       - uses: actions/setup-java@v5
         with:
           distribution: temurin
-          java-version: 21
+          java-version: 21   # keep in sync with gradle/gradle-daemon-jvm.properties
           cache: gradle
       - uses: gradle/actions/setup-gradle@v6
 
@@ -28,7 +28,7 @@ jobs:
       - uses: actions/setup-java@v5
         with:
           distribution: temurin
-          java-version: 21
+          java-version: 21   # keep in sync with gradle/gradle-daemon-jvm.properties
           cache: gradle
       - uses: gradle/actions/setup-gradle@v6
 

gradle/gradle-daemon-jvm.properties

@@ -0,0 +1,4 @@
+#
+# https://docs.gradle.org/current/userguide/gradle_daemon.html#sec:configuring_daemon_jvm
+#
+toolchainVersion=21

jitpack.yml

@@ -1,5 +1,5 @@
 jdk:
-  - openjdk21
+  - openjdk21   # keep in sync with gradle/gradle-daemon-jvm.properties
 before_install:
   - sdk install java 21.0.2-open
   - sdk use java 21.0.2-open