We're unable to hide the gradle "welcome" message on our CI server without hiding other actually useful logging.

Expected Behavior

gradle should have a flag besides -q that hides the welcome message.

Current Behavior

Currently the only way to hide the welcome message reliably is to use the -q flag, which also suppresses other logging besides the welcome message.

Context

Even though #6756 and #5213 have been fixed, there's still no way to hide the welcome message without hiding info logging entirely. The previous workaround using -Dorg.gradle.internal.launcher.welcomeMessageEnabled=false doesn't seem to work either:

$ docker run -it gradle:6.2.2-jdk8 gradle -Dorg.gradle.internal.launcher.welcomeMessageEnabled=false --version

Welcome to Gradle 6.2.2!

Here are the highlights of this release:
 - Dependency checksum and signature verification
 - Shareable read-only dependency cache
 - Documentation links in deprecation messages

For more details see https://docs.gradle.org/6.2.2/release-notes.html


------------------------------------------------------------
Gradle 6.2.2
------------------------------------------------------------

Build time:   2020-03-04 08:49:31 UTC
Revision:     7d0bf6dcb46c143bcc3b7a0fa40a8e5ca28e5856

Kotlin:       1.3.61
Groovy:       2.5.8
Ant:          Apache Ant(TM) version 1.10.7 compiled on September 1 2019
JVM:          1.8.0_242 (AdoptOpenJDK 25.242-b08)
OS:           Linux 4.19.76-linuxkit amd64

While using a file to mark whether the notification has been shown might work fine on personal development machines, it's ineffective on a CI server and results in the welcome message being shown on every build. Gradle should either detect non-interactive invocations and suppress the welcome message (#5201), or at the very least provide a flag to do so manually.