Update use_cases.md – User Personas page link

We should replace the User Personas link from the old Google Doc to the new page in the documentation. 

That said, is there a way to do this so that the link will be updated when this branch of the documentation is merged? @mrshll1001

docs/hsds/use_cases.md

@@ -11,7 +11,7 @@ Open Referral's agenda is set by the prerogatives of a set of four types of user
 * researchers/analysts;
 * database administrators. 
 
- Read more about each of these personas in [our User Personas documentation](https://docs.google.com/document/d/1aodu4BUDVbUwVD02zlFs0WkCMn3UQEX1VHyI8ej6BCU/edit). 
+ Read more about each of these personas in [our User Personas documentation]([https://docs.openreferral.org/en/documentation-review/initiative/index.html#types-of-use-and-user-personas]). 
 
 
 **Current Human Services Data Specification Capabilities**