Fix for ViaVersion autoupdate code

[Yankie]

Fixes #34

[cyberops7]

Can confirm the proposed fix results in retrieving the version properly:

❯ curl --no-progress-meter -k -L -H "Accept-Encoding: identity" -H "Accept-Language: en" -L -A "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/90.0.4.212 Safari/537.36" https://ci.viaversion.com/job/ViaVersion/lastBuild/artifact/build/libs/ | grep -P '(?<=href=")ViaVersion[^"]+' -o --max-count=1 | head -n1
ViaVersion-5.0.4-SNAPSHOT.jar

[tunafishman]

It would be great to see this get merged so that the standard docker run command in the repo readme would work again!

[TheRemote]

Accepted, thank you!