Blacklist tries to match team names perfectly

[casualinformee]

Is your feature request related to a problem? Please describe.
The blacklist feature of the script only looks for perfect matches between team names set in config.json and team names searched for in the Teams web app:

Teams-Auto-Joiner/auto_joiner.py

Line 83 in 12593e5

blacklist_item = next((bl_team for bl_team in blacklist if bl_team['team_name'] == self.name), None)

This may cause some issues if one or more characters are missing from the team_name value set by a user.

Describe the solution you'd like
I think a more user-friendly way of searching for blacklisted team names would be to see if the team_name string in config.json is contained within the actual team names searched through.

Additional context
See also: #37, where I propose the use of a whitelist instead of a blacklist to search through the appropriate teams. Note: I think the whitelist should search for relevant team names in the same way as described here (checking if team_name is contained rather than checking for an exact match ==).