Set OpenAPI version back to 6.2.1 and fix GitLab CI

patches/InviteMessageType-Display.rs

@@ -0,0 +1,10 @@
+impl std::fmt::Display for InviteMessageType {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            Self::Message => write!(f, "message"),
+            Self::Response => write!(f, "response"),
+            Self::Request => write!(f, "request"),
+            Self::RequestResponse => write!(f, "requestResponse"),
+        }
+    }
+}