Have actions/checkout clone submodules recursively in test workflows

Set `submodules: recursive` on `actions/checkout` in the three workflows
that run the test suite (cygwin-test, alpine-test, pythonpackage) so
that submodule working trees are fetched in parallel by the action,
not sequentially in `init-tests-after-clone.sh`. The script's
`git submodule update --init --recursive` line becomes a no-op
verification rather than the only mechanism for fetching submodules,
and the script's other responsibilities (master branch setup, reflog
history, version tags) are unaffected.

The codeql and lint workflows do not run the test suite and do not
need submodules; they are unchanged.

This does not eliminate the dubious-ownership issue covered by later
commits in this chain. `actions/checkout`'s `set-safe-directory: true`
default adds only the main repository path to safe.directory, and on
Cygwin that addition lands in the Windows-side global git config, not
the Cygwin-side one (since `actions/checkout` runs the Node action
against the Windows git binary, while Cygwin git uses its own global
config under the Cygwin user's home). So the cygwin-test workflow
still needs the explicit `safe.directory` entries for the gitdb and
smmap working trees that subsequent commits add.

Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: EliahKagan

.github/workflows/alpine-test.yml

@@ -29,6 +29,7 @@ jobs:
     - uses: actions/checkout@v6
       with:
         fetch-depth: 0
+        submodules: recursive
 
     - name: Set workspace ownership
       run: |

.github/workflows/cygwin-test.yml

@@ -37,6 +37,7 @@ jobs:
     - uses: actions/checkout@v6
       with:
         fetch-depth: 0
+        submodules: recursive
 
     - name: Install Cygwin
       uses: cygwin/cygwin-install-action@v6

.github/workflows/pythonpackage.yml

@@ -53,6 +53,7 @@ jobs:
     - uses: actions/checkout@v6
       with:
         fetch-depth: 0
+        submodules: recursive
 
     - name: Set up Python ${{ matrix.python-version }}
       uses: actions/setup-python@v6