Separate concurrency groups for GitHub workflows

It seems that workflows cancel each other out if they are in the same
concurrency group: https://github.com/orgs/community/discussions/41518

Try to separate four workflows that run on PRs into separate concurency
groups. Ideally this will avoid the cancelation.

They should still cancel runs from previous pushes, each in their own
group.

Author: Gabriel Erzse

.github/workflows/doctests.yml

@@ -10,7 +10,7 @@ permissions:
   contents: read
 
 concurrency:
-  group: ${{ github.event.pull_request.number || github.ref }}
+  group: ${{ github.event.pull_request.number || github.ref }}-doctests
   cancel-in-progress: true
 
 jobs:

.github/workflows/integration.yml

@@ -12,7 +12,7 @@ on:
     - cron: "0 1 * * *"
 
 concurrency:
-  group: ${{ github.event.pull_request.number || github.ref }}
+  group: ${{ github.event.pull_request.number || github.ref }}-integration
   cancel-in-progress: true
 
 jobs:

.github/workflows/linter.yaml

@@ -3,7 +3,7 @@ name: Format check on pull request
 on: pull_request
 
 concurrency:
-  group: ${{ github.event.pull_request.number || github.ref }}
+  group: ${{ github.event.pull_request.number || github.ref }}-linter
   cancel-in-progress: true
 
 jobs:

.github/workflows/spellcheck.yml

@@ -4,7 +4,7 @@ on:
   pull_request:
 
 concurrency:
-  group: ${{ github.event.pull_request.number || github.ref }}
+  group: ${{ github.event.pull_request.number || github.ref }}-spellcheck
   cancel-in-progress: true
 
 jobs: