SessionExpiryInterval does not result in sessions being expired

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Describe the bug

When a client establishes a session using SessionExpiryInterval > 0, and then disconnects, then later reconnects with CleanSession=false, it does not matter if the session expiry interval has lapsed, the client will resume the prior session.

Which component is your bug related to?

• Server

To Reproduce

Steps to reproduce the behavior:

1. Using MQTTNet v4.2.1.781
2. Connect a client with a specific ClientID, setting SessionExpiryInterval to 1.
3. Subscribe to a topic
4. Disconnect your client
5. Send messages to the topic subscribed in 3
6. Wait as long as you'd like past your SessionExpiryInterval
7. Re-connect your client with CleanSession=false

Expected behavior

Client connects, is given a new session because the prior session has expired.

Actual behavior

Client connects and resumes prior session, receives all pending messages.

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Note https://docs.oasis-open.org/mqtt/mqtt/v5.0/os/mqtt-v5.0-os.html#_Storing_Session_State:~:text=The%20Server%20MUST%20discard%20the%20Session%20State%20when%20the%20Network%20Connection%20is%20closed%20and%20the%20Session%20Expiry%20Interval%20has%20passed%20%5BMQTT%2D4.1.0%2D2%5D.