Specify the path to the Java SDK used for the Android gradle build

Introduce an editor setting to allow users the ability to specify the path to the Java SDK used for the Android gradle build.

platform/android/java/app/build.gradle

@@ -241,3 +241,12 @@ task copyAndRenameReleaseAab(type: Copy) {
     into getExportPath()
     rename "build-release.aab", getExportFilename()
 }
+
+/**
+ * Used to validate the version of the Java SDK used for the Godot gradle builds.
+ */
+task validateJavaVersion {
+    if (JavaVersion.current() != versions.javaVersion) {
+        throw new GradleException("Invalid Java version ${JavaVersion.current()}. Version ${versions.javaVersion} is the required Java version for Godot gradle builds.")
+    }
+}

platform/android/java/app/config.gradle

@@ -9,7 +9,7 @@ ext.versions = [
     kotlinVersion      : '1.7.0',
     fragmentVersion    : '1.3.6',
     nexusPublishVersion: '1.1.0',
-    javaVersion        : 17,
+    javaVersion        : JavaVersion.VERSION_17,
     // Also update 'platform/android/detect.py#get_ndk_version()' when this is updated.
     ndkVersion         : '23.2.8568313'