Yargs causing npm audit warnings

[taylortom]

Summary from npm:

Moderate	Inefficient Regular Expression Complexity in chalk/ansi-regex
Package	ansi-regex
Patched in	>=5.0.1
More info	GHSA-93q8-gq69-wqmw

Issue looks to be fixed in yargs 15+ (guessing 16+ will be a no-go for you guys atm as it drops node v10 support).

[taylortom]

Just spotted this #153

[sy-records]

Thanks for your feedback, I will merge them.