build: Updates for Go 1.19.

[lukebp]

Depends on #1673.

This commit updates the repo to use Go 1.18 and 1.19.

• The CI is updated to use Go 1.18 and 1.19. Go 1.17 is removed.
• The following Github Actions are updated. The pinned hashes are used to help prevent supply chain attacks. https://github.com/actions/setup-go/commit/84cbf8094393cdc5fe1fe1671ff2647332956b1a #v3.2.1 https://github.com/actions/checkout/commit/2541b1294d2704b0964813337f33b291d3f8596b #v3.0.2
• golangci-lint is updated v1.48.0.
• The READMEs are updated to reflect Go 1.18 and 1.19.
• go.mod is updated to Go 1.18 and a go tidy is run.