Support Go 1.18, phase out Go 1.16

[lukasmalkmus]

This PR makes sure the package builds fine with the recent Go 1.18. As we just support the lst two minor releases of Go, I'll dropped support for Go 1.16. But as this only affects some toolchain related changes, it will continue to build under Go 1.16 (and possibly lower).

Needs golangci/golangci-lint#2438 to pass CI.

[kamstrup]

Uh, I did not know about t.Cleanup(f) nice! This bump is ok by me, as long as we agree to not introduce any sweeping changes with any or or type params.

[lukasmalkmus]

This bump is ok by me, as long as we agree to not introduce any sweeping changes with any or or type params.

We won't, as axiom-go is supposed to support the last two minor versions of Go, which is now 1.17 and 1.18. In around half a year, when Go 1.19 comes around, we'll go that route and introduce any over interface{} and see if we can use some fancy 1.18 features. This PR is just in draft as we need an upstream fix for golangci-lint.

So this PR only makes sure we build fine with Go 1.18 (which was expected, tbh) and drops some of the outdated, pre 1.17 build tags.

Uh, I did not know about t.Cleanup(f) nice!

This has actually been around since Go 1.14. Pretty neat! You might also want to checkout Go 1.17's T.Setenv method.

[codecov]

Codecov Report

Merging #106 (dcee784) into main (e77ec89) will increase coverage by 0.02%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main     #106      +/-   ##
==========================================
+ Coverage   71.85%   71.87%   +0.02%     
==========================================
  Files          41       41              
  Lines        1304     1305       +1     
==========================================
+ Hits          937      938       +1     
  Misses        222      222              
  Partials      145      145              

Impacted Files	Coverage Δ
axiom/client.go	80.88% <100.00%> (+0.14%)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update efc8339...dcee784. Read the comment docs.

[github-actions]

This PR/issue depends on:

• go1.18 support golangci/golangci-lint#2438
  By Dependent Issues (🤖). Happy coding!