fix(deps): bump actions/setup-node from v1 to v2.1.2

Bumps [actions/setup-node](https://github.com/actions/setup-node) from v1 to v2.1.2.
- [Release notes](https://github.com/actions/setup-node/releases)
- [Commits](actions/setup-node@v1...c6fd00c)

Signed-off-by: dependabot[bot] <support@github.com>

.github/workflows/openapi.yml

@@ -11,7 +11,7 @@ jobs:
         uses: actions/checkout@v1
 
       - name: Use Node.js 12.x
-        uses: actions/setup-node@v1
+        uses: actions/setup-node@v2.1.2
         with:
           node-version: 12.x