Apply suggested fix to mixin.go from Copilot Autofix

Co-authored-by: Copilot Autofix powered by AI <223894421+github-code-quality[bot]@users.noreply.github.com>

Author: fredbi

mixin.go

@@ -130,6 +130,7 @@ func pathItemOps(p spec.PathItem) []*spec.Operation {
 	rv = appendOp(rv, p.Post)
 	rv = appendOp(rv, p.Delete)
 	rv = appendOp(rv, p.Head)
+	rv = appendOp(rv, p.Options)
 	rv = appendOp(rv, p.Patch)
 
 	return rv