commonlogger.rb - fix HIJACK time format, use constants, not strings

[MSP-Greg]

Description

Current log output from a request and a 'full-hijacked' request:

127.0.0.1 - - [08/Feb/2023:18:47:21 -0600] "GET /users/profiles HTTP/1.1" 200 - 0.1126
127.0.0.1 - - [08/Feb/2023 18:47:22] "GET /cable HTTP/1.1" HIJACKED -1 0.6079

Note the hijack log line doesn't have a time zone offset...

Fixed and used constants for the env keys instead of strings. Not sure if local constants are better than using one from Puma::Const?

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[nateberkopec]

Log formatting is so sensitive sometimes, I feel like we have to consider this a breaking change.

[dentarg]

Log formatting is so sensitive sometimes, I feel like we have to consider this a breaking change.

Then we ought to have tests covering this? Only implementation changed here

Also, isn't this a bugfix? Bug fixes always have the potential to be breaking for someone

[nateberkopec]

Alright, you convinced me 😆