gitlab-ci: Upload build reports as artifacts as well

These contains important reports like lint which is useful for
debugging issues
Signed-off-by: Aayush Gupta <theimpulson@e.email>

.gitlab-ci.yml

@@ -14,4 +14,4 @@ build:
   artifacts:
     paths:
     - app/build/outputs/apk/
-  
\ No newline at end of file
+    - app/build/reports/
\ No newline at end of file