actions: add "pipefail" protection to tests

Author: oliver-sanders

.github/workflows/tests.yml

@@ -17,7 +17,7 @@ env:
 
 defaults:
   run:
-    shell: micromamba-shell {0}
+    shell: bash -c "exec $CONDA_PREFIX/bin/bash -elo pipefail {0}"
 
 jobs:
   test:
@@ -36,7 +36,6 @@ jobs:
       - name: Configure Python
         uses: mamba-org/setup-micromamba@v2
         with:
-          generate-run-shell: true
           cache-environment: true
           post-cleanup: 'all'
           environment-name: cylc
@@ -122,7 +121,6 @@ jobs:
       - name: Configure Python
         uses: mamba-org/setup-micromamba@v2
         with:
-          generate-run-shell: true
           cache-environment: true
           post-cleanup: 'all'
           environment-name: cylc