Update src/content/docs/identityserver/upgrades/v7_2-to-v7_3.md

Author: maartenba

src/content/docs/identityserver/upgrades/v7_2-to-v7_3.md

@@ -34,7 +34,7 @@ For example in your project file:
 would change to:
 
 ```xml
-<PackageReference Include="Duende.IdentityServer" Version="7.3.0" />
+<PackageReference Include="Duende.IdentityServer" Version="7.3.0-rc.1" />
 ```
 
 ## Step 2: Breaking Changes