Reproduction steps:
1. Open the attached user's project "Photon-Pun2-Deploy.zip"
2. Block port 5058 in the Firewall or a network tool
3. Open the Scene "MinimalConnect" and Build and Run it as Standalone IL2CPP build
4. When the client runs, give it maybe a second to try to connect, then click the "Disconnect" button
5. Open the Profiler, you can see the spike of one second and explore into the place where it is (Check attached Profiler.png)

Expected result: As the protocol is not connection-oriented, a connection close without delay is expected
Actual result: If the connection is blocked and the user / logic calls Socket.Close() (or Socket.Close(0)) at that moment, this results in a 1 second blocking operation deeper in Socket.Dispose()

Reproduces on: 2019.4.30f1, 2020.3.22f1, 2021.1.18f1, 2021.2.0b12, 2022.1.0a9

Notes:
-The issue is NOT present when using Socket.Send and Socket.BeginReceive