feat(common): git hash info func

[joremysh]

Because

• it helps in debugging with the current running version

This commit

• add function for reading git hash

[linear]

INS-6693 unit tests for pipeline backend

[jvallesm]

nit: even if it duplicates the return "" line, a guard error clause makes the code more readable by indenting the non-happy paths.

Suggested change

	if info, ok := debug.ReadBuildInfo(); ok {
	for _, setting := range info.Settings {
	if setting.Key == "vcs.revision" {
	return setting.Value
	}
	}
	}
	return ""
	info, ok := debug.ReadBuildInfo()
	if !ok {
	return ""
	}
	for _, setting := range info.Settings {
	if setting.Key == "vcs.revision" {
	return setting.Value
	}
	}
	return ""

[jvallesm]

Can you document this exported variable? Some interesting things to say about it:

• Why this is needed / when it should be used
• An example of how it can be used (e.g. a log method call)