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Add check for bad ports to http_fetch(), return NetworkError::Internal if bad port/schema combination is seen.
Test added
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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#14514 (github issue number if applicable).
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- [x] There are tests for these changes OR
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