[APC] Add a function to reduce repetition in the `pingset red|orange|green` commands

[Vexed01]

What cog is this feature request for?

AnotherPingCog

Describe the feature request in as much detail as possible

There is a lot of code repetition in pingset red, pingset orange and pingset green in anotherpingcog.py. This could be cleaned up and made easier to maintain by adding a function which is called by all three.

This is one of my Hacktoberfest issues, which anyone may take without needing to ask me directly, and if not done I will get around to doing them in the coming months.