Test wheel build on PR (temp ... undo later).

Updates to wheel workflow:

* Build for Py 3.10 via linux action shell script.
  This was missed in #928 and is needed for #918
* Fix missing git history needed for setuptools_scm
  to do its thing for Linux wheels

Apply fix used in msprime.

Don't unshallow...

try path for macos work flow?

.github/workflows/manylinux/buildwheels.sh

@@ -13,8 +13,15 @@ cd gsl-${GSL_VERSION}
 make -j 2 
 make install 
 cd .. 
+
+# Taken from msprime/#2043
+# We're running as root in the docker container so git commands issued by
+# setuptools_scm will fail without this:
+git config --global --add safe.directory /project
+# Fetch the full history as we'll be missing tags otherwise.
+# git fetch --unshallow
 
-for py in cp37-cp37m cp38-cp38 cp39-cp39
+for py in cp37-cp37m cp38-cp38 cp39-cp39 cp310-cp310
 do
     PYPATH=/opt/python/${py}
     PYBIN=${PYPATH}/bin/python 

.github/workflows/wheels.yml

@@ -5,6 +5,9 @@ on:
     - cron: "0 0 1 * *"
   release:
     types: [created]
+  pull_request:
+  push:
+    branches: [main, dev]
 
 jobs:
   macOS:
@@ -117,6 +120,7 @@ jobs:
         uses: actions/download-artifact@v2
         with:
           name: macOS-wheel-${{ matrix.python }}
+          path: dist
       - name: Set up Python ${{ matrix.python }}
         uses: actions/setup-python@v2
         with: