Builds on GitHub master branch are fine, but checkout for PRs does not seem work correctly

CircleCI works great as long as I build from the master branch of my GitHub project, however, when CircleCI is started due to a new PR, it seems that the checkout goes wrong. I cannot fully interpret the output, but it seems to me that the working directory does not seem to be in the correct state, e.g. my circle.yml file is not present, and as a consequence, the whole build goes south because CircleCI does not know my settings.

An example of this would be: https://circleci.com/gh/dbmanul/dbmanul/253

Quoting the (hopefully) relevant section from the log:

Checkout using CircleCI fork PR checkout user key: 72:[…]config
Warning: Permanently added ‘github.com,192.30.253.112’ (RSA) to the list of known hosts.

remote: Counting objects: 9, done.
remote: Compressing objects: 100% (4/4), done.
remote: Total 9 (delta 5), reused 8 (delta 4), pack-reused 0
Unpacking objects: 100% (9/9), done.
From github.com:dbmanul/dbmanul

  • [new ref] refs/pull/35/head -> origin/pull/35
    MACHINE
    Configure the build
    Suppressing export of environment variables SONARQUBE_TOKEN fork PR builds00:00UI
    Restore cache
    No cache is used
    mvn dependency:go-offline
    [this one does not go through because it cannot resolve dependencies between submodules of my project]

I am a little confused as to why the dependency:go-offline is executed. It does not seem to happen on my regular builds, and I am pretty sure I do not start it from my circle.yml.