Set the shell to bash

.github/workflows/build.yaml

@@ -78,6 +78,7 @@ jobs:
           export PKG_CONFIG_PATH="/usr/local/opt/icu4c/lib/pkgconfig:/opt/homebrew/opt/icu4c/lib/pkgconfig${PKG_CONFIG_PATH+:$PKG_CONFIG_PATH}";
           export PATH="/usr/local/opt/icu4c/bin:/usr/local/opt/icu4c/sbin${PATH+:$PATH}"
           python -m tox r -m build
+        shell: bash
 
       - name: Archive production artifacts
         uses: actions/upload-artifact@v3

.github/workflows/package.yaml

@@ -46,6 +46,7 @@ jobs:
           export PATH="/usr/local/opt/icu4c/bin:/usr/local/opt/icu4c/sbin${PATH+:$PATH}"
           python -m tox r
           python -m tox r -m release
+        shell: bash
         env:
           TWINE_USERNAME: __token__
           TWINE_PASSWORD: ${{ secrets.PYPI_API_TOKEN }}