Removed integrity check and test for no-cors requests
Removed Step 30.2 which raised a JS TypeError if the integrity metadata was not empty. I manually ran `new Request("", {"mode" : "no-cors", "integrity" : "not an empty string"});` in servo to validate that the exception no longer arose.
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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#18345
- [x] These changes do not require tests because according to the ticket "Unfortunately, there's no automated test available for this yet because we are having trouble updating our copy of the upstream tests. "
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e6099b4364
