Handle temperature exactly 0 degrees

[forslund]

Description

This friday my Mark-1 gave a slightly odd answer when asked about the weather conditions, "... and degrees." he said and showed a screen with the snowflake symbol but no number.

Seems like the criteria is a bit too general and will consider a temperature of 0 as a false value and replace it with the empty string.

This PR corrects the behavior here, checking explicitly for None instead.

Type of PR

• [x] Bugfix
• [ ] Feature implementation
• [ ] Refactor of code (without functional changes)
• [ ] Documentation improvements
• [ ] Test improvements

[krisgesling]

Ha - good fix. Definitely never going to hit that here :sun_with_face:

Stay warm!