gh-211: cancel intermediate builds + don't fetch entire git history

.github/workflows/test.yml

@@ -8,6 +8,12 @@ on:
     branches:
     - main
 
+concurrency:
+  # Skip intermediate builds: always.
+  # Cancel intermediate builds: only if it is a pull request build.
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: ${{ startsWith(github.ref, 'refs/pull/') }}
+
 jobs:
 
   style:
@@ -25,8 +31,6 @@ jobs:
         python-version: ['3.8', '3.9', '3.10', '3.11', '3.12']
     steps:
     - uses: actions/checkout@v4
-      with:
-        fetch-depth: 0
     - uses: actions/setup-python@v5
       with:
         python-version: ${{ matrix.python-version }}
@@ -38,17 +42,13 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v4
-      with:
-        fetch-depth: 0
     - run: pipx run build
 
   docs:
     name: Docs
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v4
-      with:
-        fetch-depth: 0
     - run: |
         sudo apt-get update
         sudo apt-get install pandoc
@@ -59,8 +59,6 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v4
-      with:
-        fetch-depth: 0
     - uses: actions/setup-python@v5
       with:
         python-version: "3.x"