fix: Some bad math with the JitterBuffer sequence tracking

[thatsnotright]

Description

I'm not sure what I was thinking, uint16 should wrap itself correctly.

Reference issue

Fixes #253

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 72.45%. Comparing base (142f17f) to head (9814d5f).

Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #254 +/- ## ========================================== + Coverage 72.39% 72.45% +0.05% ========================================== Files 79 79 Lines 3648 3648 ========================================== + Hits 2641 2643 +2 + Misses 870 869 -1 + Partials 137 136 -1 ``` | [Flag](https://app.codecov.io/gh/pion/interceptor/pull/254/flags?src=pr&el=flags&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pion) | Coverage Δ | | |---|---|---| | [go](https://app.codecov.io/gh/pion/interceptor/pull/254/flags?src=pr&el=flag&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pion) | `72.45% <100.00%> (+0.05%)` | :arrow_up: | | [wasm](https://app.codecov.io/gh/pion/interceptor/pull/254/flags?src=pr&el=flag&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pion) | `70.55% <100.00%> (ø)` | | Flags with carried forward coverage won't be shown. [Click here](https://docs.codecov.io/docs/carryforward-flags?utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pion#carryforward-flags-in-the-pull-request-comment) to find out more.

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[thatsnotright]

@Sean-Der Can you let me know if this PR is good to go? Thanks!