Remove outdated Vagrantfile
Remove outdated Vagrantfile

It still contained JDK 7 whereas the plugin already requires JDK 8.

kamilszymanski/job-dsl-plugin,daspilker/job-dsl-plugin,jenkinsci/job-dsl-plugin,daspilker/job-dsl-plugin,daspilker/job-dsl-plugin,kamilszymanski/job-dsl-plugin,kamilszymanski/job-dsl-plugin,jenkinsci/job-dsl-plugin,jenkinsci/job-dsl-plugin