fix lock to prerelease in CI

Author: bckohan

.github/workflows/test.yml

@@ -331,11 +331,12 @@ jobs:
       - name: Setup Just
         uses: extractions/setup-just@v3
       - name: Install Release Dependencies
+        shell: bash
         run: |
           just setup ${{ steps.sp.outputs.python-path }}
           if [[ "${{ matrix.django-version }}" =~ (a|b|rc) ]]; then
             # prerelease, use exact version pin
-            just test-lock Django==${{ matrix.django-version }}.0
+            just test-lock Django==${{ matrix.django-version }}
           else
             # stable release, use compatible release specifier
             just test-lock Django~=${{ matrix.django-version }}.0