test: skip flaky test

This needs some additional investigation, I was not able to reproduce
the failure in local.

Author: darrachequesne

Diff for: test/index.ts

@@ -320,7 +320,7 @@ describe("@socket.io/postgres-adapter", () => {
       servers[0].disconnectSockets();
     });
 
-    it("sends a packet before all socket instances disconnect", (done) => {
+    it.skip("sends a packet before all socket instances disconnect", (done) => {
       const partialDone = times(3, done);
 
       clientSockets.forEach((clientSocket) => {