TargetCommitish falls back to default `master` / default branch

[Larusso]

atlas-plugins/src/main/groovy/wooga/gradle/plugins/PluginsPlugin.groovy

Line 260 in c38e2e1

releaseName.set(project.provider {project.version.toString()})

We don't explicitly set the targetCommitish property which creates issues if we release from a release/1.x branch.