message: Fixes typo in link #trivial [skip ci]
diff: # Adding a Lab Option
  -[This doc has moved here](./development_a_feature.md), but [cool URLs don't change](https://www.w3.org/Provider/Style/URI), so we keep this document around.
  +[This doc has moved here](./developing_a_feature.md), but [cool URLs don't change](https://www.w3.org/Provider/Style/URI), so we keep this document around.
  