Rename eq_ignore_case to starts_with_ignore_case

[gabriel-doriath-dohler]

The method doesn't test for equality. It tests if the object starts with
a given byte array, so its name is confusing.

[rust-highfive]

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[rust-highfive]

Thanks for the pull request, and welcome! The Rust team is excited to review your changes, and you should hear from @joshtriplett (or someone else) soon.

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[joshtriplett]

@bors r+

[bors]

📌 Commit 2626531 has been approved by joshtriplett

[bors]

⌛ Testing commit 2626531 with merge cdd74fc...

[bors]

☀️ Test successful - checks-actions
Approved by: joshtriplett
Pushing cdd74fc to master...

[rust-timer]

Finished benchmarking commit (cdd74fc): comparison url.

Summary: This benchmark run did not return any relevant results.

If you disagree with this performance assessment, please file an issue in rust-lang/rustc-perf.

@rustbot label: -perf-regression