feat: Deprecate and replace Bool,Int,Int64,String with Ptr using generics

[alexandear]

This PR proposes adding a new helper routine github.Ptr that can be used instead of existing github.Bool, github.Int, github.Int64, github.String.

NOTE that this PR bumps the minimum required version of Go from 1.17 to 1.18.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 92.33%. Comparing base (2b8c7fa) to head (5ea1286).
Report is 175 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #3355      +/-   ##
==========================================
- Coverage   97.72%   92.33%   -5.39%     
==========================================
  Files         153      176      +23     
  Lines       13390    15097    +1707     
==========================================
+ Hits        13085    13940     +855     
- Misses        215     1064     +849     
- Partials       90       93       +3     

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[gmlewis]

I have mixed feelings about this change.

While I'm a huge fan of generics, that would change our base requirements of this repo from a minimum Go version of 1.17 to 1.18, if I'm not mistaken.

I have not heard any requests to maintain support for old versions of Go, and we have always officially tested the most recent release of Go and the prior minor version.

Let's see if this generates any discussion, pro or con.

Meanwhile, if we move forward with this, we should probably convert all the existing usages to Ptr.

[gmlewis]

OK, I'm reviewing now. Please refrain from force-pushing if possible, as we always squash-and-merge in this repo so the commit history will be clean, and this will make reviewing changes in the PR much easier for the reviewer(s). Thanks.

[gmlewis]

Thank you, @alexandear !
LGTM.

Awaiting second LGTM+Approval from any other contributor to this repo before merging (along with any discussion for or against this change, as usual, of course).

[alexandear]

Just for the reference: xanzy/go-gitlab deprecated gitlab.String, gitlab.Bool, gitlab.Int in favor of gitlab.Ptr in xanzy/go-gitlab#1788 one year ago.