Add golangci-lint to CI process

[algochoi]

Problem

Supercedes #168

We want to enforce a linter in the Go SDK repo, just like our other repos.

Solution

• Add reviewdog/action-golangci-lint@v2 Github Actions workflow
  • We can enforce it after a particular commit hash, and slowly fix existing lint errors over time or just fix those errors at once.
• Add a .golangci.yml file (use Conduit configurations as an example)
  • We should exclude generated files from linters as we cannot control those
• Use golangci-lint in the make lint step. We can also add a go vet step.

Considerations:

• Have a clean git history by hiding lint commits, see this
  • Github seems to natively support this now: https://docs.github.com/en/repositories/working-with-files/using-files/viewing-a-file#ignore-commits-in-the-blame-view
• Split up linting PRs