Un-redact safe request/response headers in HttpLoggingMiddleware

[wtgodbe]

Fixes #36156 based on decisions made about safe headers for Yarp by @samsp-msft. Here's an example console log, from the SignalR SocialWeather sample:

info: Microsoft.AspNetCore.HttpLogging.HttpLoggingMiddleware[1]
Request:
Protocol: HTTP/1.1
Method: GET
Scheme: http
PathBase:
Path: /weather
Connection: Upgrade
Host: localhost:5000
User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/92.0.4515.159 Safari/537.36
Accept-Encoding: gzip, deflate, br
Accept-Language: en-US,en;q=0.9
Cache-Control: no-cache
Origin: [Redacted]
Pragma: [Redacted]
Upgrade: websocket
Sec-WebSocket-Version: [Redacted]
Sec-WebSocket-Key: [Redacted]
Sec-WebSocket-Extensions: [Redacted]

info: Microsoft.AspNetCore.HttpLogging.HttpLoggingMiddleware[2]
Response:
StatusCode: 101
Connection: [Redacted]
Date: Wed, 08 Sep 2021 22:42:54 GMT
Server: Kestrel
Upgrade: [Redacted]
Sec-WebSocket-Accept: [Redacted]

[wtgodbe]

CC @blowdart - any concerns on these?

[Tratcher]

Request:
Sec-WebSocket-Version
Sec-WebSocket-Extensions

Response:
Connection
Upgrade

[wtgodbe]

Any concerns with Sec-WebSocket-Version or Sec-WebSocket-Extensions @blowdart?

[sebastienros]

What is a "safe" header. One that doesn't contain personal information?

[blowdart]

Nope, no concerns

[wtgodbe]

What is a "safe" header. One that doesn't contain personal information?

Yes

[wtgodbe]

/backport to release/6.0

[github-actions]

Started backporting to release/6.0: https://github.com/dotnet/aspnetcore/actions/runs/1218231063