Renaming a global using alias does not update usages

**Version Used**:
17.11.0 Preview 3.0

**Steps to Reproduce**:
Test1.cs
```cs
global using MyInteger = int; // Rename here…
```
Test2.cs
```cs
public class C {
public MyInteger M() => 42; // …or here
}
```
Rename the `MyInteger` using alias in any of the two places.

**Expected Behavior**:
The using alias should be updated in both places.

**Actual Behavior**:
Only the using alias declaration is updated. This looks especially weird when you start the rename from the usage.