Fix broken project board links in CONTRIBUTING.md and README.md

[xyzqm]

Description

Fix two broken project board links in CONTRIBUTING.md and README.md.

I'm not entirely sure which pages each link was originally supposed to link to, so I just made my best guess.

Checklist

• [x] I read and understood the contributing guide as well as the code of conduct
• [x] The issues this PR addresses are related to each other
• [x] My changes generate no new warnings
• [x] My code builds and runs on my machine
• [x] My changes are all related to the related issue above
• [x] I documented my code

Screenshots

[xyzqm]

Hi @austincondiff, could you take a look at this? (Sorry, I'm not quite sure who to ping for review 😓 )