Stop bumping go directive unless necessitated by other dependencies

[kaovilai]

Stop bumping go directive unless necessitated by other dependencies :)

Sorry for bugging again @cpanato :)

Originally posted by @kaovilai in f78a69f

toolchain version used will be defined outside of go.mod ideally, such as by installing a newer compatible go toolchain to ci/cd/development env.

Failing that, toolchain directive should be used instead of go directive for bumping versions to not cascade minimum versions to importing dependencies.

toolchain directive, in contrast to the go directive, applies only to the current module (the one defined by the go.mod file). It suggests the toolchain to be used when in that very module, and doesn't propagate to other modules.

[kaovilai]

Oops fixed in main :)

#1879