Test enable groups as specified by PR labels (#2357)

* Allow CIBW_ENABLE to control the wheels built in testing

* Set CIBW_ENABLE using PR labels

* Add docs

* Build everything on the main branch

* Add CIBW_ENABLE=all option

This was mostly for use in the `main` building case, because otherwise it's maybe a bit too easy to forget to update this file when adding an enable group

* Remove dead code

* Make unit tests robust to the value of CIBW_ENABLE

* Fix tests that explicitly choose pypy

* Fix test expectation

* Don't expect impossible wheels in expected_wheels

* Simplify logic in expected_wheels

* CircleCI- run with CIBW_ENABLE=all only on the main branch

* Azure pipelines - run with CIBW_ENABLE=all on main branch

* Update gitlab to run CIBW_ENABLE=all on main

* Set CIBW_ENABLE=all on travis - it only runs on main anyway

* Fix job name error on CircleCI

* Fix tests for graalpy

* Update the test configuration to use the label

* Remove duplication of default value. Make it affect sample build too

* Move the action to after deps are installed

* GraalPy workaround for this assumption

* Make unit test resilient to changing CIBW_ENABLE

azure-pipelines.yml

@@ -16,6 +16,12 @@ jobs:
         docker run --rm --privileged docker.io/tonistiigi/binfmt:latest --install all
         python -m pip install dependency-groups
         python -m dependency_groups test | xargs python -m pip install -e.
+        if [ "$(Build.SourceBranch)" = "refs/heads/main" ]; then
+          echo "INFO: Exporting CIBW_ENABLE=all for main branch test run."
+          export CIBW_ENABLE=all
+        else
+          echo "INFO: CIBW_ENABLE not set for this branch ($(Build.SourceBranch))."
+        fi
         python ./bin/run_tests.py
 
 - job: macos_311
@@ -28,6 +34,12 @@ jobs:
     - bash: |
         python -m pip install dependency-groups
         python -m dependency_groups test | xargs python -m pip install -e.
+        if [ "$(Build.SourceBranch)" = "refs/heads/main" ]; then
+          echo "INFO: Exporting CIBW_ENABLE=all for main branch test run."
+          export CIBW_ENABLE=all
+        else
+          echo "INFO: CIBW_ENABLE not set for this branch ($(Build.SourceBranch))."
+        fi
         python ./bin/run_tests.py
 
 - job: windows_311
@@ -40,4 +52,10 @@ jobs:
     - bash: |
         python -m pip install dependency-groups
         python -m dependency_groups test | xargs python -m pip install -e.
+        if [ "$(Build.SourceBranch)" = "refs/heads/main" ]; then
+          echo "INFO: Exporting CIBW_ENABLE=all for main branch test run."
+          export CIBW_ENABLE=all
+        else
+          echo "INFO: CIBW_ENABLE not set for this branch ($(Build.SourceBranch))."
+        fi
         python ./bin/run_tests.py