Auto merge of #18247 - Majora320:master, r=emilio

Silenced camel case warning for the iOS enum variant

Fix a simple warning.
---
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors

This change is obviously too trivial for tests.

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components/config/opts.rs

@@ -448,6 +448,7 @@ pub fn multiprocess() -> bool {
 enum UserAgent {
     Desktop,
     Android,
+    #[allow(non_camel_case_types)]
     iOS
 }