Feature request: Allow category names to not be unique if their types are different

[Picardyn73]

Please confirm you have done the following before posting your bug report:

• I have enabled debug mode
• I have read checked the Common Issues page

Describe the bug
A clear and concise description of what the bug is.

To Reproduce
Steps to reproduce the behavior:

1. Go to 'Asset Categories'
2. Click on 'Create New'
3. Create a new Categorie of a type not equal to an Asset.
4. Now in the overview it will not be listed (not correct)
5. Create now a new Category of the same name with a different category and an error will appear that the Asset Category already exists (not correct also since it is a different category.

Expected behavior
See all newly created Categories
Able to have same name for different categories when the type is not the same

Screenshots
If applicable, add screenshots to help explain your problem.

Server (please complete the following information):

• Snipe-IT Version Version v5.1.2 - build 5847 (master)

Desktop (please complete the following information):

• OS: MacOS
• Browser Chrome Version 89.0.4389.90 (Official Build) (x86_64) / Safari Version 14.0.3 (16610.4.3.1.7)