Renaming request with colon ( : ) in name breaks the bru file

[pelicanny]

Tested in Bruno 1.6.1

Steps to recreate:

1. create POST request in bruno desktop app with name "My request"
2. context menu click request and rename
3. enter new name "My request with a : colon in the name"
4. File disappears in bruno
5. File is broken (.bru disappeared and simply adding it again does not make it reappear in bruno)

Thanks for the great work you are doing! 🥇

[Its-treason]

This is probably a Windows problem, because : is not allowed as a file name in NTFS. #349 should fix this, but I need to rewrite the PR.