docs: abs link for do.rq (#806)

This is needed as the file is not present on docs.styra.com

Signed-off-by: Charlie Egan <[email protected]>

docs/CONTRIBUTING.md

@@ -19,7 +19,7 @@ Recommended, but not required:
 
 - The [rq](https://git.sr.ht/~charles/rq) tool. This is used for automating and simplifying many of the tasks outlined
  in this document, and is (ab)used as a Rego-based replacement for Make in this project. Check out the
- [do.rq](../build/do.rq) file to see what that looks like, and for documentation on the available tasks.
+ [do.rq](https://github.com/StyraInc/regal/blob/main/build/do.rq) file to see what that looks like, and for documentation on the available tasks.
 
 ## Contributing New Rules