android: check if native modules assets exist

Checks if the native modules assets folder exists before trying
to create the files and dir lists for the current arch at build time.
Fixes a build error when trying to build with the native modules
feature turned on but without native modules inside the nodejs
project.

android/build.gradle

@@ -325,6 +325,10 @@ if ("1".equals(shouldRebuildNativeModules)) {
             outputs.file "${rootProject.buildDir}/nodejs-native-assets/nodejs-native-assets-${abi_name}/file.list"
             outputs.file "${rootProject.buildDir}/nodejs-native-assets/nodejs-native-assets-${abi_name}/dir.list"
             doLast{
+                if(!(new File("${rootProject.buildDir}/nodejs-native-assets/nodejs-native-assets-${abi_name}/")).exists()) {
+                    // If the native assets folder doesn't exist from the copy task, skip the creation of the file.list
+                    return;
+                }
                 delete "${rootProject.buildDir}/nodejs-native-assets/nodejs-native-assets-${abi_name}/file.list"
                 delete "${rootProject.buildDir}/nodejs-native-assets/nodejs-native-assets-${abi_name}/dir.list"
                 String file_list = "";