Resotre java min compatible to 21 and remove 24 (#902)

Signed-off-by: Peter Zhu <[email protected]>

Author: peterzhuamazon

.github/workflows/gradle.yml

@@ -13,7 +13,7 @@ jobs:
     strategy:
       matrix:
         java:
-          - 24
+          - 21
           - 25
       fail-fast: false
     runs-on: [ubuntu-latest]

.github/workflows/maven-publish.yml

@@ -20,7 +20,7 @@ jobs:
       - uses: actions/setup-java@v3
         with:
           distribution: temurin # Temurin is a distribution of adoptium
-          java-version: 25
+          java-version: 21
       - uses: actions/checkout@v3
 
       - name: Load secret

build.gradle

@@ -140,12 +140,9 @@ opensearchplugin {
     classname = 'org.opensearch.performanceanalyzer.PerformanceAnalyzerPlugin'
 }
 
-def javaVersion = JavaVersion.current().isCompatibleWith(JavaVersion.VERSION_25) ?
-        JavaVersion.VERSION_25 : JavaVersion.VERSION_21
-
 java {
-    sourceCompatibility = javaVersion
-    targetCompatibility = javaVersion
+    sourceCompatibility = JavaVersion.VERSION_21
+    targetCompatibility = JavaVersion.VERSION_21
 }
 
 compileJava {