build: upgrade go version to 1.18

[takclark]

trafficstars

GitHub Action tests have been failing since this run. It's caused by dependency on strings.Cut, which was added in 1.18 and appeared in dependency https://github.com/docker/cli some time between v20.10.17 and v24.0.1.

So, go 1.18 is the minimum required version here. This should fix the tests.

Related Issue or Design Document

Checklist

• [x] I have read the contributing guidelines and signed the CLA.
• [ ] I have referenced an issue containing the design document if my change introduces a new feature.
• [x] I have read the security policy.
• [x] I confirm that this pull request does not address a security vulnerability. If this pull request addresses a security vulnerability, I confirm that I got approval (please contact [email protected]) from the maintainers to push the changes.
• [ ] I have added tests that prove my fix is effective or that my feature works.
• [ ] I have added the necessary documentation within the code base (if appropriate).

Further comments

[takclark]

and you can now see "Nancy" failing on the runc version because of CVE-2024-21626, which I would also like to fix

[alnr]

We're now on Go 1.21