Categories with dots are not created in the correct space

To reproduce

1. XWiki version: 9.2
2. Log as admin and open the blog application categories management page 'Blog.ManageCategories'
3. Click on 'Add a category' button, fill the 'New category' field with a category name that contains dots (ex: Category1.1)
4. Click on the 'Add' button to save the category

Expected result: the new category is created and added under the 'Blog' space (Blog/Category1.1)
Current result: the category is created but the space is not correct, the category is created under the space 'Blog.Category1' (Blog.Category1/1)

To fix this escape the name of the category before saving it.