ci: fix env install

Author: lkstrp

.github/workflows/test.yaml

@@ -53,8 +53,8 @@ jobs:
 
     - name: Use base env file if it was changed
       run: |
-        git fetch origin master
-        if git diff --name-only origin/master | grep '${{ env.BASE_ENV }}'; then
+        git fetch origin ${{ github.event.repository.default_branch }}
+        if git diff --name-only origin/${{ github.event.repository.default_branch }} | grep '${{ env.BASE_ENV }}'; then
           echo "Base env ${{ env.BASE_ENV }} changed. Using it instead of locked envs."
           echo "env_file=${{ env.BASE_ENV }}" >> $GITHUB_ENV
         else