[Razor] CSS Isolation not working when special characters in project name

### Is there an existing issue for this?

- [x] I have searched the existing issues

### Describe the bug

When having (space, dash, underline) in project name, CSS Isolation won't work.
Tested by an empty ASP.NET Core MVC project with .NET 6.
First made a project named "MVC CSS-Isolation" but it didn't work and getting error "MVC_CSS_Isolation.css 404 not found" in browser console.
After that, made another project name "MVCIsolation" and CSS Isolation worked fine.

### Expected Behavior

_No response_

### Steps To Reproduce

_No response_

### Exceptions (if any)

_No response_

### .NET Version

6.0.201

### Anything else?

_No response_