Explicitly specify android:exported to activity-alias

[codekarma]

:loudspeaker: Type of change

• [ X] Bugfix
• [ ] New feature
• [ ] Enhancement
• [ ] Refactoring

:scroll: Description

Added android:exported attribute to the activity-alias element.

:bulb: Motivation and Context

android:exported should be explicitly specified to activity-alias element(just like activity, service and receiver) when the corresponding component has an intent filter defined. This will be enforced in the future version of AGP.

:green_heart: How did you test it?

:pencil: Checklist

• [ ] I ran ./gradlew spotlessApply before submitting the PR
• [ ] I reviewed submitted code
• [ ] I added tests to verify changes
• [ ] All tests passing

:crystal_ball: Next steps

:camera_flash: Screenshots / GIFs