ci: Install [email protected] for macOS

This commit updates the CI workflow to install the Python 3.10 package
for macOS because the current sdk-build-macos image only contains Python
3.8.

This should be reverted once the sdk-build-macos image is updated to
include the `[email protected]` package by default.

Signed-off-by: Stephanos Ioannidis <[email protected]>

Author: stephanosio

.github/workflows/ci.yml

@@ -538,6 +538,10 @@ jobs:
                        gnu-sed gnu-tar help2man meson ncurses ninja pkg-config
         fi
 
+        # Install Python 3.10 (temporary until the sdk-build-macos image is
+        # updated)
+        brew install [email protected]
+
         # Install dependencies for cross compilation
         if [ "${{ matrix.host.name }}" == "macos-x86_64" ]; then
           # Make crosskit available in PATH