Suggestion: Update RFC Reference for HTTP Authentication

[konradzagozda]

Hello,

While reading through this section, I noticed that RFC 7235 is referenced as the source for HTTP Authentication definition.

I wanted to suggest updating the reference to RFC 9110, which has officially obsoleted RFC 7235. While I haven’t compared the definitions in detail, encountering an obsolete RFC might be slightly discouraging for readers who are new to the topic.