chore: bump go to 1.18

[cmwaters]

No description provided.

[mark-rushakoff]

I'm not sure why the linter started complaining about these existing lines -- maybe the new indirect entries in go.mod updated a version of a linter unexpectedly?

+1 to moving to go1.18 anyway.

[cmwaters]

level=warning msg="[linters context] gosimple is disabled because of go1.18. You can track the evolution of the go1.18 support by following the https://github.com/golangci/golangci-lint/issues/2649."
  level=warning msg="[linters context] staticcheck is disabled because of go1.18. You can track the evolution of the go1.18 support by following the https://github.com/golangci/golangci-lint/issues/2649."
  level=warning msg="[linters context] structcheck is disabled because of go1.18. You can track the evolution of the go1.18 support by following the https://github.com/golangci/golangci-lint/issues/26[49](https://github.com/tendermint/tendermint/runs/7612082007?check_suite_focus=true#step:5:51)."
  level=warning msg="[linters context] stylecheck is disabled because of go1.18. You can track the evolution of the go1.18 support by following the https://github.com/golangci/golangci-lint/issues/2649."
  level=warning msg="[linters context] unused is disabled because of go1.18. You can track the evolution of the go1.18 support by following the https://github.com/golangci/golangci-lint/issues/2649."

Seems like a lot of the linting stuff was deprecated in go1.18

[mark-rushakoff]

We are on v1.47.2 of golangci-lint, and v1.47.3 was released two hours ago, including golangci/golangci-lint#3001 to "remove some go1.18 limitations". Shouldn't hurt to update to that newer patch release.

[mark-rushakoff]

bodyclose support is supposed to be re-enabled as part of golangci-lint v1.47.3, according to golangci/golangci-lint#3001.

[mark-rushakoff]

New updates still LGTM.