CI: Fix pytest collection error

Author: namannimmo10

.github/workflows/main-checks.yml

@@ -42,6 +42,10 @@ jobs:
           pip install .[dev]
           micromamba list
 
-      - name: Run all tests (including Zenodo)
+      - name: Run small data tests
         run: |
-          pytest tests/ zenodo-tests/
+          pytest tests/
+
+      - name: Run Zenodo tests
+        run: |
+          pytest zenodo-tests/