Actual Behaviour
Travis build scripts were based on relative paths and changing of directories and hence, after the PR #2013, it can't reference to built files
Expected Behaviour
Either travis scripts should reference correct relative paths or preferably use absolute paths so that the directory containing scripts do not have any significance in build process
Reference
Last build on Travis : https://travis-ci.org/fossasia/open-event-android/builds/316025286?utm_source=github_status&utm_medium=notification
@iamareebjamal I think path of generated apks is changed in latest build tools.

So we need to update paths in generate_apks.sh from app/build/outputs/apk/app-{fdroid/googleplay}-{debug/release}.apk to app/build/outputs/apk/{fdroid/googleplay}/{debug/release}/app-{fdroid/googleplay}-{debug/release}.apk
OR Update the path of generated apks
Also https://travis-ci.org/fossasia/open-event-android/builds/316025286#L2179 is uses rm to delete generated apks. But now apks are in sub directories so we need to use rm -R to delete all the sub directories and files
Thanks @Shailesh351 馃槃