Feature: add option to not rebuild with newer toolchain

[yukita443]

Is your feature request related to a problem?

An option to prevent unintended rebuilds caused by toolchain updates would be useful, especially if the user has a large number of packages installed.

Describe the solution you'd like

Adding an option like gup update --ignore-go-update

Describe alternatives you've considered

Installing a binary per go toolchains installed by asdf.

Additional context

#154

[nao1215]

@yukita443
Thank you for the suggestion of a new feature !!
I couldn't fully understand the use case, so I have a few questions.

Here is the use case I imagined:

• You are developing multiple projects, each using a different Go version.
• When you run go generate ./... for a project, you want to match the "Go version for the project" with the "Go version used to build the binaries under $GOPATH/bin."

Is this the situation you are referring to? I personally think it's fine to always use the latest Go version, so I’m not quite sure I understand your ideal situation.

Also, does the --ignore-go-update option skip the update only when the Go toolchain is updated? For example, if the toolchain becomes outdated, will gup still skip the update? Which of these behaviors is the feature you are requesting?