When combining multiple filters for a search (searchTracks) with a "+", this must not be encoded.

[STARSCrazy]

Describe the bug
If you combine multiple filters in a search (searchTracks), the "+" is also encoded, although this is not supposed to be so according to the documentation: https://developer.spotify.com/documentation/web-api/reference/#/operations/search

To Reproduce
spotify.searchTracks("track:Lithium+artist:Nirvana+album:Nevermind");
How the request url actually looks like: search/?q=track%3ALithium%2Bartist%3ANirvana%2Balbum%3ANevermind&type=track
How it should look like: search/?q=track%3ALithium+artist%3ANirvana+album%3ANevermind&type=track