Print warning when passing an unknown type to list command

[Floriszenz]

This PR improves the list command to print a warning message when passing an unknown category type as filter. The output will be:

$ npx picco ls --type=feature --type=unknown
┌   picco list
│
▲  Ignoring unknown category type "unknown"
│  Valid types are: "feature", "bugfix", "refactor", "performance", "dependencies", "removal", "migration", "documentation", "other"
│
●  Features
│  • Feature 1
│  • Feature 2
│
└   Have a nice day!

Closes #3

[adi64]

Works as described 👍