ci: fixup

Author: toshimaru

.github/workflows/ci.yml

@@ -61,7 +61,12 @@ jobs:
         with:
           submodules: true
       - name: fetch Rails tags
-        run: cd rails && git fetch --depth=1 origin refs/tags/v8*:refs/tags/v8* refs/tags/v6*:refs/tags/v6* refs/tags/v5*:refs/tags/v5*
+        run: |
+          cd rails && git fetch --depth=2 origin \
+            refs/tags/v8*:refs/tags/v8* \
+            refs/tags/v8*:refs/tags/v7* \
+            refs/tags/v6*:refs/tags/v6* \
+            refs/tags/v5.2*:refs/tags/v5.2*
       - uses: ruby/setup-ruby@v1
         with:
           ruby-version: 2.7