ci: lint, format and test in github actions

.github/workflows/lint-and-format.yml

@@ -1,6 +1,6 @@
 name: Lint and Format
 on:
-  pull_request:
+  pull_request_target:
     branches:
       - main
 

.github/workflows/test.yml

@@ -1,9 +1,13 @@
 name: Tests / Backend
 on:
-  pull_request:
+  pull_request_target:
     branches:
       - main
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
 jobs:
   postgres-container:
     runs-on: ubuntu-latest