increase upper limit of heap memory

otherwise
./gradlew clean assemble --refresh-dependencies

threw

e: java.lang.OutOfMemoryError: GC overhead limit exceeded

Signed-off-by: Marcel Hibbe <dev@mhibbe.de>

gradle.properties

@@ -17,7 +17,7 @@
 
 # Specifies the JVM arguments used for the daemon process.
 # The setting is particularly useful for tweaking memory settings.
-org.gradle.jvmargs=-XX:MaxHeapSize\=2048m -Xmx2048m
+org.gradle.jvmargs=-XX:MaxHeapSize\=4096m -Xmx4096m
 org.gradle.dependency.verification.console=verbose
 
 android.useAndroidX=true