Update build-mosdns.yml

.github/workflows/build-mosdns.yml

@@ -32,11 +32,13 @@ jobs:
         with:
           ref: mosdns
           path: mosdns
+      - name: Clean mosdns branch
+        if: github.event_name == 'schedule'
+        continue-on-error: true
+        run: rm mosdns/*
       - name: Rebuild mosdns branch
         if: github.event_name == 'schedule'
-        run: |
-          rm mosdns/*
-          ./exp_mosdns.sh
+        run: ./exp_mosdns.sh
       - name: Push to mosdns branch
         if: github.event_name == 'schedule'
         continue-on-error: true