Add kotlinOptions jvmTarget to templates (#147326)

Adds jvmTarget to gradle templates. 

Fixes https://github.com/flutter/flutter/issues/147185.

Interestingly, we already had this in many of our examples/tests, see search results here https://github.com/search?q=repo%3Aflutter%2Fflutter%20jvmTarget&type=code.

dev/integration_tests/android_semantics_testing/android/app/build.gradle

@@ -4,8 +4,8 @@
 
 plugins {
     id "com.android.application"
-    id "dev.flutter.flutter-gradle-plugin"
     id "kotlin-android"
+    id "dev.flutter.flutter-gradle-plugin"
 }
 
 def localProperties = new Properties()
@@ -25,6 +25,10 @@ android {
         targetCompatibility JavaVersion.VERSION_1_8
     }
 
+    kotlinOptions {
+        jvmTarget = JavaVersion.VERSION_1_8
+    }
+
     defaultConfig {
         minSdkVersion flutter.minSdkVersion
         targetSdkVersion flutter.targetSdkVersion