Distinguish 5.10 from 5.1!

Author: daveverwer

.github/workflows/ci.yml

@@ -23,7 +23,8 @@ jobs:
   run-tests:
     strategy:
       matrix:
-        swift-version: [5.6, 5.7, 5.8, 5.9, 5.10]
+        # We don't need anything specific in 5.10.1, but 5.10 collapses to 5.1 when `swift-setup` runs.
+        swift-version: [5.6, 5.7, 5.8, 5.9, 5.10.1]
     runs-on: ubuntu-20.04
     steps:
       - uses: actions/checkout@v4