Let the entire job fail when one strategy fails (#529)

Before the entire job counted as success, even with individual
strategies failing.

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Co-authored-by: Adrian Catangiu <adrian@parity.io>
Co-authored-by: fellowship-merge-bot[bot] <151052383+fellowship-merge-bot[bot]@users.noreply.github.com>

Author: 3 people

.github/workflows/check-migrations.yml

@@ -44,9 +44,10 @@ jobs:
   # if they all pass, that job will pass too.
   check-migrations:
     needs: [runtime-matrix]
-    continue-on-error: true
     runs-on: ubuntu-latest
     strategy:
+      # Ensure the other jobs continue
+      fail-fast: false
       matrix:
         runtime: ${{ fromJSON(needs.runtime-matrix.outputs.runtime) }}
     steps: