Try prune in find

Author: Katharine Hyatt

.github/workflows/Tests.yml

@@ -29,7 +29,7 @@ jobs:
         shell: bash
         run: |
           # Auto-discover test groups from all subdirectory names.
-          groups=$(find test -mindepth 1 -maxdepth 1 -type d \
+          groups=$(find test -mindepth 1 -maxdepth 1 -type d -name testsuite -prune -o \( \! -name '*~' -print0 \) \
             | xargs -I{} basename {} | sort \
             | jq -R -s -c '[split("\n")[] | select(length > 0)]')