[Request] Merge apk architecture picker flag

[chaixshot]

For example, the size of org.mozilla.firefox_beta_151.0b1.apkm is 270MB. And after merged is 560MB
So, add a flag to pick only the wanted architecture to reduce file size and return an error if that architecture does not exist.

[REAndroid]

This may widen our project scope but good to have this feature, lets keep open this issue

(Btw its hustle but for workaround: you can extract to folder >> keep only preferred files >> pass the folder to merge)