Don't test all feature flags

Author: richardpringle

.github/workflows/tests.yaml

@@ -270,7 +270,7 @@ jobs:
 
       - name: Run unit tests
         run: |
-          cargo nextest run --workspace --lib --all-features \
+          cargo nextest run --workspace --lib \
               --exclude mina-core \
               --exclude mina-fuzzer \
               --exclude mina-macros \