Update gpg output on "How to verify Tor Browser signature"

https://support.torproject.org/tbb/how-to-verify-signature/

$ gpg --auto-key-locate nodefault,wkd --locate-keys torbrowser@torproject.org

gpg: key 4E2C6E8793298290: "Tor Browser Developers (signing key) <torbrowser@torproject.org>" 2 new signatures
gpg: Total number processed: 1
gpg:         new signatures: 2
pub   rsa4096 2014-12-15 [C] [expires: 2025-07-21]
      EF6E286DDA85EA2A4BA7DE684E2C6E8793298290
uid           [ unknown] Tor Browser Developers (signing key) <torbrowser@torproject.org>
sub   rsa4096 2018-05-26 [S] [expires: 2020-12-19]