I opened a pull request (#888 #890) that only changed the README. The Travis automatic build failed with the error:
[ERROR] Failed to execute goal org.apache.maven.plugins:maven-deploy-plugin:2.7:deploy (default-deploy) on project Vault: Failed to deploy artifacts: Could not transfer artifact net.milkbowl.vault:Vault:jar:1.7.3 from/to pub-repo (http://nexus.hc.to/content/repositories/pub_releases/): Transfer failed for https://nexus.hc.to/content/repositories/pub_releases/net/milkbowl/vault/Vault/1.7.3/Vault-1.7.3.jar 401 Unauthorized -> [Help 1]

This (obviously) builds fine on my computer. I have no idea what could have caused this. Considering that the last commit to this repository was in August 2021, maybe something needs to be updated? It looks like all of the other pull request builds are failing too.

EDIT: #888 no longer only changes the README, but it did at the time of this error
EDIT 2: #890 is a good example of this issue

I have a few one explaination to the builds failing issue:

• A) Due to a lack of knowledge PRs are built and deployed to the pub_repo, but somehow the system is configured to reject deployments for PR builds (note that there was never a PR that suceeded building without modifying significant chunks of the deployment code)

Considering that deployment is an irrelevant part of the build for PRs it might make sense to use the package goal instead of the deploy goal but that might require more configuration or was just not possible at the time travis was set up. However just ignoring the issue and looking where the build fails might have been sufficient up until now and given that you should never change a running system it was not altered.

It looks like there is an if statement in the build script to skip deployment if it isn't a release build, however, even after I tried updating it (you can see the changes in #888), it still didn't work.

#893 resolved this issue.