Java 21 instead of 11

Author: mkurz

.github/workflows/build-test.yml

@@ -27,7 +27,7 @@ jobs:
     name: Docs
     uses: playframework/.github/.github/workflows/cmd.yml@v4
     with:
-      java: 17, 11
+      java: 21, 17
       scala: 2.13.x, 3.x
       cmd: cd docs && sbt ++$MATRIX_SCALA validateCode
 
@@ -39,7 +39,7 @@ jobs:
       - "check-docs"
     uses: playframework/.github/.github/workflows/cmd.yml@v4
     with:
-      java: 17, 11
+      java: 21, 17
       scala: 2.13.x, 3.x
       cmd: >-
         sbt ++$MATRIX_SCALA test
@@ -52,7 +52,7 @@ jobs:
       - "check-docs"
     uses: playframework/.github/.github/workflows/cmd.yml@v4
     with:
-      java: 17, 11
+      java: 21, 17
       scala: 2.13.16, 3.3.4
       cmd: >-
         sbt "