chore(deps): Use golangci-lint from nixpkgs

[jonstacks]

What

We have several places where we manage dependencies. We have some currently consumed via nix, some via github actions, some via Makefile, and naturally our go dependencies. Having to update our Makefile dependencies periodically as opposed to just running nix flake update like we already do for go version increases complexity. We're looking at moving many of these to nix and out of go tools where appropriate.

How

• Pull golangci-lint from nixpkgs instead of via makefile
• Updates CI to install nix so that golangci-lint is on the path for make lint
• As part of using the nix provided golangci-lint, we're using version 2 of golangci-lint now, so this updates the .golangci-lint version to match

Breaking Changes

No, this is an internal build system only change

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 48.86%. Comparing base (4d223a0) to head (0dc6cbf).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #725      +/-   ##
==========================================
- Coverage   48.94%   48.86%   -0.08%     
==========================================
  Files          95       95              
  Lines       10594    10594              
==========================================
- Hits         5185     5177       -8     
- Misses       5046     5053       +7     
- Partials      363      364       +1     

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[alex-bezek]

Should we also update this contributing guide for the non-nix users to have a list of things you need to install manually https://github.com/ngrok/ngrok-operator/tree/main/docs/developer-guide#non-codespaces

[jonstacks]

Should we also update this contributing guide for the non-nix users to have a list of things you need to install manually https://github.com/ngrok/ngrok-operator/tree/main/docs/developer-guide#non-codespaces

Good call out. Updated the developer documentation