github/workflows: add concurrency groups

This will cancel any ongoing workflows when we update a pull request.

Author: dlech

.github/workflows/codeql-analysis.yml

@@ -20,6 +20,10 @@ on:
   schedule:
     - cron: '19 21 * * 4'
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
 jobs:
   analyze:
     name: Analyze

.github/workflows/test-pull-request.yml

@@ -7,6 +7,10 @@ on:
   pull_request:
     branches: [ master ]
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
 jobs:
   test: