openapi{2,3}: add 2-3k OpenAPI documents test suite

Signed-off-by: Pierre Fenoll <pierrefenoll@gmail.com>

Author: fenollp

.github/workflows/shellcheck.yml

@@ -0,0 +1,18 @@
+name: ShellCheck
+
+on:
+  push:
+  pull_request:
+
+jobs:
+  shellcheck:
+    runs-on: ubuntu-latest
+    steps:
+    - name: Checkout
+      uses: actions/checkout@v2
+
+    - name: Run shellcheck
+      uses: ludeeus/action-shellcheck@1.1.0
+      with:
+        check_together: 'yes'
+        severity: error