Remove duplicated issue state copy

This handbook page had two very similar blurbs right next to each other:

"Generally speaking, issues are in one of two states:

• Discovery/refinement: we're still answering questions that prevent us from starting development,
• Implementation: an issue is waiting for an engineer to work on it, or is actively being built."

and

"Generally speaking, issues are in one of two states:

• "Figuring it out": we're still answering questions that prevent us from starting development,
• "Build it": an issue is waiting for an engineer to work on it, or is actively being built."

I like the wording of the first one but the section of the page that the second was in.