Update AndroidManifest.xml for Android S

[caraesten]

The latest version of Android requires all activities that use an intent-filter to specify whether or not they're exported (https://developer.android.com/about/versions/12/behavior-changes-12#exported).

Currently, anyone using filestack-android will have their build broken when compiling for S

[shiik0]

Hi!

I'm working on an application that is aiming for the version 32 of the android SDK, so the master branch breaks my build currently. Already tested the branch from this PR and now everything is working properly! So it would be great if this PR is merged. Is that possible?

@scana I noticed that you made the last release. Are you the maintainer of this project or can you point me to who is the current maintainer? Much appreciated 😄

[scana]

@shiik0 hi! Sorry, I am no a longer maintainer of this project - not sure if anyone took over after I left.

I would suggest forking this repository on your own or contacting user support through https://www.filestack.com/.

As an alternative, you can re-declare this Activity in your main AndroidManifest.xml and the end result should be merged:

<activity
  android:name="com.filestack.android.FsActivity"
  android:exported="true"/>