[test] Regression Tests for TCP

[ppenna]

Description

We should add the following regression tests for TCP:

• [ ] Deterministic hashmap
• [ ] Random number of clients, connecting and disconnecting from each other randomly
• [ ] Futzing for sending data, receiving data, half-closing, full-closing
• [ ] Delay, drop, reorder, and duplicate packets randomly
• [ ] Different MSS and TCP options
• [ ] Invariant checks around resources getting freed
• [ ] Resource limit scenarios