*: add exit_code check for zh link checking (#370)

.github/workflows/link-check.yaml

@@ -16,20 +16,21 @@ jobs:
       #  - we use `http://172.*` as sample addresses in some docs, so we need to exclude them.
       - name: Check external links in zh files
         uses: peter-evans/link-checker@v1
+        id: lczh
         with:
           args: -c 32 -d /github/workspace -r -x "http://172.*|https://github.com/pingcap/dm/pull/.*|.*.md" zh*
 
       - name: Check external links in en files
-        id: lc
+        id: lcen
         uses: peter-evans/link-checker@v1
         with:
           args: -c 32 -d /github/workspace -r -x "http://172.*|https://github.com/pingcap/dm/pull/.*|.*.md" en*
 
       - name: Fail if there were external link errors
-        if: ${{ steps.lc.outputs.exit_code }}
+        if: ${{ steps.lczh.outputs.exit_code || steps.lcen.outputs.exit_code }}
         run: |
           echo "Please check the broken links reported in previous steps \"Check external links in zh files\" and \"Check external links in en files\"."
-          exit ${{ steps.lc.outputs.exit_code }}
+          exit ${{ steps.lczh.outputs.exit_code || steps.lcen.outputs.exit_code }}
 
       # Debug via SSH if previous steps failed
       #- name: Set up tmate session