Extra build from master on release tag should not upload non-snapshot artifacts

[szpak]

When an extra build from master on release tag is performed (e.g. having cron buildiing the latest commit in master) the non-snapshot artifacts should not be uploaded. It creates a complicit Nexus repository which breaks the following build.

Sample cron job: https://travis-ci.org/szpak/mockito-java8/jobs/352115159

Possible extra check:

✔ in release branch
  ✘ not CRON build

[szpak]

Possible workaround:

//Some workarounds on CDeliveryBoy limitations - #3 and #13 (see below)

//Note. Referring non built-in types in external build script is problematic: https://github.com/gradle/gradle/issues/1262
//Note2. Task dependency removal is problematic due to: https://github.com/gradle/gradle/pull/6143/
["uploadArchives", "createRepository", "pointUploadArchivesToExplicitRepository"].each { String taskName ->
    tasks.named(taskName).configure {
        onlyIf {
            boolean onlyIfValue = resolveOnlyIfValueForUploadTasks()
            if (!onlyIfValue) {
                logger.lifecycle("Task disabled due to environment settings for ciBuild")
            }
            return onlyIfValue
        }
    }
}

boolean resolveOnlyIfValueForUploadTasks() {
    return !isSnapshotBuildWithSkipReleaseOnCI() && !isExtraBuildOfReleaseTagOnCI()
}
//Workaround on https://github.com/szpak/CDeliveryBoy/issues/3 - do not upload snapshots from other Java versions on CI server
boolean isSnapshotBuildWithSkipReleaseOnCI() {
    return (project.version as String).endsWith("-SNAPSHOT") && System.env.SKIP_RELEASE == "true" && isCiBuildTaskCalled()
}
//Workaround on https://github.com/szpak/CDeliveryBoy/issues/13 - do not upload artifacts on extra build on CI server (e.g. from cron) of release tag
boolean isExtraBuildOfReleaseTagOnCI() {
    return !(project.version as String).endsWith("-SNAPSHOT") && !ciBuild.inReleaseMode && isCiBuildTaskCalled()
}
boolean isCiBuildTaskCalled() {
    //It covers only basic (idiomatic) case that "ciBuild" task has been called directly. Examining taskGraph would be better, however, more problematic due to late preparation.
    return gradle.startParameter.taskNames.contains("ciBuild")
}