servo: Merge #14282 - Fix out-of-date link in documentation (from staktrace:doc-fix); r=emilio

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The documentation referenced has moved, so the link needs to be updated.

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- [ ] These changes fix #__ (github issue number if applicable).

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Source-Repo: https://github.com/servo/servo
Source-Revision: dd611ef310159ff3de5e7117186504c050ddb02e

servo/docs/HACKING_QUICKSTART.md

@@ -123,7 +123,7 @@ paths = ['../glutin', '../cocoa-rs']
 
 This will tell any cargo project to not use the online version of the dependency, but your local clone.
 
-For more details about overriding dependencies, see [Cargo's documentation](http://doc.crates.io/guide.html#overriding-dependencies).
+For more details about overriding dependencies, see [Cargo's documentation](http://doc.crates.io/specifying-dependencies.html#overriding-dependencies).
 
 ## Debugging