Ensure compatibility with [email protected] on platform Android

[UNIDY2002]

Since AGP v8, the default value of android.buildFeatures.buildConfig has been changed to false. (See: https://developer.android.com/build/releases/past-releases/agp-8-0-0-release-notes#default-changes)
RN 73 has upgraded AGP to v8.
Since we are using the buildConfigField() method, upgrading RN to 73 will cause this module to throw an error during building:

A problem occurred configuring project ':react-native-webview'.
> defaultConfig contains custom BuildConfig fields, but the feature is disabled.
  To enable the feature, add the following to your module-level build.gradle:
  `android.buildFeatures.buildConfig true`

Therefore, this PR sets the value of android.buildFeatures.buildConfig to true.

[UNIDY2002]

It seems that this issue can be solved on RN's side, so let's just wait at the moment.

• Enable build config feature for third-party libraries facebook/react-native#40791

[UNIDY2002]

Update: it is required that each library adapt to this change in AGP.

So this PR remains necessary.

[UNIDY2002]

This issue is fixed on RN side by facebook/react-native@db45da7.
Closing this PR.