Improve URL detection to support unencoded non-ASCII characters

K9-Mail builds links incorrectly. Thats very annoying when there is a mail from url watch like "CHANGED: Google (https://www.google.de/maps)" You can click that link but URL won't be found because there is a closing bracket at the end of the URL and that can't work

Expected behavior

Link is correctly build

Actual behavior

A closing bracket is appended to the link

Steps to reproduce

1. Send a text only mail like "See here (https://www.google.de/maps)"
2. View that E-Mail in K9-Mail and click the link. You'll get an error not found because it tries to open "https://www.google.de/maps)"
3. Interesstingly when sending "See here (https://www.google.de)" it works correctly, so as soon there is a slash / in the URL K9 doesn't build the URL correct any more. Thunderbird does it by the way.
   You can send that text only mail by
   echo "See here (https://www.google.de/maps)" | mail -s test yourmail@company.com

Environment

K-9 Mail version:
5.600
Android version:
8.0.0
Account type (IMAP, POP3, WebDAV/Exchange):
IMAP
Please take some time to retrieve logs and attach them here:

Reproduce the issue using the provided plain-text email and compare links containing a path with links ending at the domain. Start by tracing K-9 Mail's URL detection and link-building path; done means the closing parenthesis is excluded from the link and the reproduced URL opens correctly.