Added Websocket to RequestMode enum
Added Websocket to RequestMode enum
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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix#14785 (github issue number if applicable).
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- [ ] There are tests for these changes OR
- [x] These changes do not require tests because matching the enum should have default control flow.
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