CI: enable test and lint for PRs from forks.

.github/workflows/lint.yml

@@ -1,6 +1,8 @@
 name: Linting
 
-on: [ push ]
+on:
+  push:
+  pull_request_target:
 
 jobs:
   analyse:

.github/workflows/test.yml

@@ -1,6 +1,9 @@
 #https://github.com/marketplace/actions/android-emulator-runner
 name: Test
-on: [ push ]
+on:
+  push:
+  pull_request_target:
+
 jobs:
   test:
     timeout-minutes: 45