* Update CI Go version to 1.20/1.19
* Update `golangci-lint` to v1.51.2
* Update coverage collection to use new Go 1.20 tools
* Update coverage job to only run on latest Go version
Fixes#367
Use bot app token for third-party metadata tests.
These tests have hit HTTP 403 errors, speculated due to hitting restrictive
rate limits. Github app tokens have much higher rate limits.
* Bump CI to Go 1.19
* Update golang/go edwards25519 test
* Apply formatting to printer stubs output (to get correct comment formatting)
* Bump gofumpt version
