Update gitlab-metrics-exporter version

What does this MR do and why?

This release brings in:

• Make golang 1.20.4 the default for development (gitlab-metrics-exporter!42 (merged))
• Bump go to 1.19.9 (gitlab-metrics-exporter!41 (merged))
• Bump Go x-sys to latest version (gitlab-metrics-exporter!40 (merged))
• Update go.mod to Go 1.19 (gitlab-metrics-exporter!39 (merged))
• Add Go 1.19 and 1.20 support (gitlab-metrics-exporter!38 (merged))
• Makefile: Don't use hardcoded path to Bash shell (gitlab-metrics-exporter!37 (merged))

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.