chore: Use local gcl to create custom gcl if on path

[stevehipwell]

This PR updates the setup-custom-gcl.sh script to use the golangci-lint on the path if it's v2. It also updates the golangci-lint config for gofumpt to replace the deprecated settings with the latest pattern.

[gmlewis]

This PR updates the setup-custom-gcl.sh script to use the golangci-lint on the path if it's v2. It also updates the golangci-lint config for gofumpt to replace the deprecated settings with the latest pattern.

You said what this is doing, but not why we need to use golangci-lint on the path - is this to avoid installing a local copy in bin? And if so, is this to save disk space?

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 98.59%. Comparing base (48d0a66) to head (678748f).

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #4600   +/-   ##
=======================================
  Coverage   98.59%   98.59%           
=======================================
  Files         197      197           
  Lines       18326    18326           
=======================================
  Hits        18068    18068           
  Misses        258      258           

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[stevehipwell]

@gmlewis I'd rather not run untrusted install scripts directly from the internet, especially when I've already got the binary on my machine. I've been manually working around this for a while now, but I was on the train yesterday on a new machine without a connection and had to mess around to get linting working so decided to fix it.

[gmlewis]

LGTM.

cc: @Not-Dhananjay-Mishra

[Not-Dhananjay-Mishra]

LGTM

[gmlewis]

Thank you, @Not-Dhananjay-Mishra!
Merging.