Https required to download from maven

[trojanc]

When trying to run any of the server docker builds, it fails with

Step 4/19 : RUN wget -q http://repo1.maven.org/maven2/org/ehcache/ehcache-clustered/3.8.0/ehcache-clustered-3.8.0-kit.tgz   && mkdir /terracotta   && tar xvzf ehcache-clustered-3.8.0-kit.tgz -C /terracotta --strip-components=1   && rm ehcache-clustered-3.8.0-kit.tgz
 ---> Running in 9dba37f832e1
wget: server returned error: HTTP/1.1 501 HTTPS Required

This was for 5.6.4 but I see the other versions also has the same line. Adding https to the url solves it