Android: Fix NPE when proxy interface method has no arguments

JDK contract: InvocationHandler.invoke's args parameter is null when
the proxied interface method takes no arguments. The proxy handlers
in AndroidRuntimePlugin used `*args` directly, which spread-deref'd
null and threw NullPointerException.

Signed-off-by: Muteem <29696635+Muteem@users.noreply.github.com>

platform/android/java/lib/src/main/java/org/godotengine/godot/plugin/AndroidRuntimePlugin.kt

@@ -86,7 +86,7 @@ class AndroidRuntimePlugin(godot: Godot) : GodotPlugin(godot) {
 
 					// Invocation for the interface single abstract method falls here and is dispatched to the
 					// Godot [Callable].
-					else -> godotCallable.call(*args)
+					else -> godotCallable.call(*(args ?: emptyArray()))
 				}
 			}
 		}
@@ -111,7 +111,7 @@ class AndroidRuntimePlugin(godot: Godot) : GodotPlugin(godot) {
 
 					// Invocation for the remaining interface(s) methods falls here and is dispatched to the
 					// Godot Object.
-					else -> Callable.call(godotObjectID, methodName, *args)
+					else -> Callable.call(godotObjectID, methodName, *(args ?: emptyArray()))
 				}
 			}
 		}