chore: upgrade to jdk21

Author: ktor

.github/workflows/build.yml

@@ -13,10 +13,11 @@ jobs:
             -   uses: actions/checkout@v4
                 with:
                     fetch-depth: 0  # Shallow clones should be disabled for a better relevancy of analysis
-            -   name: Set up JDK 11
+            -   name: Set up JDK 21
                 uses: actions/setup-java@v4
                 with:
-                    java-version: 11
+                    distribution: 'temurin'
+                    java-version: 21
             -   name: Cache SonarCloud packages
                 uses: actions/cache@v4
                 with:

.github/workflows/sonarcloud.yml

@@ -20,10 +20,11 @@ jobs:
       - uses: actions/checkout@v4
         with:
           fetch-depth: 0  # Shallow clones should be disabled for a better relevancy of analysis
-      - name: Set up JDK 11
+      - name: Set up JDK 21
         uses: actions/setup-java@v4
         with:
-            java-version: 11
+            distribution: 'temurin'
+            java-version: 21
       - name: Cache Maven packages
         uses: actions/cache@v4
         with: