[PWI-1849][Henrico] feat!: add thread-safe config implementation and upgrade to gomod

[ricoferdian-gtf]

Background

Current config map cache implementation is not thread-safe, concurrent map write could trigger fatal panic. The goal of this change is to implement thread-safe config map by using mutex approach.

Minimal changes is recommended to ensure seamless integration with latest goconfig library on client side.

Feature changes

• Implement thread-safe config map cache to address issues when config getters were called from goroutine
• Set minimum go version to 1.18 (released in 2022)

Chores

• v2 release candidate, package renamed to goconfig/v2
• Upgrade from glide to go modules
• Add actions pipeline to run tests

Notes

• minimum go version supported in GTF infrastructure is go 1.13
• minimum go version officially supported in arm-based mac is go 1.16

[tejasjadhav]

question: Do we need to update the README as well?

[ricoferdian-gtf]

question: Do we need to update the README as well?

oh yeah, turns out we don't have readme. Let me update it as well

[ricoferdian-gtf]

will add readme at the very end