go: update references to use go 1.15

[cpanato]

In the GH actions, it is already using go 1.15.x was missing to update go in two places.

/assign @jonjohnsonjr

[imjasonh]

Does it make sense to include 1.16 as well?

[cpanato]

if all agree I can update all the references to be 1.16

[jonjohnsonjr]

Let's stick with 1.15 for now? We used to have a matrix of tests in travis, but we've lost that. If we could test both 1.15 and 1.16, I'd be happy.

[cpanato]

@jonjohnsonjr i can look and implement the CI GO test matrix using GitHub actions

[jonjohnsonjr]

That would be phenomenal -- we dropped travis in #922

[cpanato]

gently ping @jonjohnsonjr

[jonjohnsonjr]

I'm not 100% clear on what the go version really means in go.mod. Is it the minimum version at which the module will build? When are you supposed to update it? It's hard to google for this stuff :/

[cpanato]

me too, but I use that to set my env to the appropriate go version

but I think that implies to the minimum go version that is required

[jonjohnsonjr]

I found golang/go#30791 which seems to agree but I haven't read the whole thing.

Do we know the minimum go version? I'm reluctant to bump this unless we really need to, because it might break folks on go1.14 for no reason...

[cpanato]

I dont have strong opinions. feel free to close this PR if you want

[cpanato]

@jonjohnsonjr I will close this PR, if we decided to update the references I can make another one

[jonjohnsonjr]

Thanks - I think we'll want to bump eventually, but I don't have any kind of policy for compatibility with go versions in mind quite yet.

[jonjohnsonjr]

Actually... I'd be happy to bump the version used in the release to 1.16, given that there are some performance improvements in the compiler from 1.14 -> 1.15 and 1.15 -> 1.16.

My only issue is with the go.mod thing, I think.