Plugin cannot be created when adding the "-" character

Repro Rate: 10/10

This issue occurred in the live build of //UE5/Release-5.1 at CL 23058290.

This was regression tested against //UE5/Release-5.0 at CL 20979098 and is confirmed to not be a regression since the issue also occurs in this build.

Customer Description:

Plugin names with a minus character result in failure and perhaps with other special characters, but the GUI doesn't warn about it nor stop the user from attempting to create a new plugin. Perhaps it was intended to work with minus signs, underscore does work. 

Steps:

1. Create a new C++ project.
2. Go to Edit > Plugins.
3. Click the Add button.
4. Select Blank as the template.
   • Other templates also share this issue except for Content Only.
5. Name the plugin with a "-" character.
   • e.g. Plugin-Name, PluginName-, etc.
6. Create the Plugin.

Actual Result: Error, failure to create plugin.

Expected Result: Attempting to create a plugin with the minus character in its name should result in either an error warning about using an invalid filename or allow the user to successfully create the plugin.