SonarQube plugin for Gradle

[Jacques Le Roux]

Hi,

Just stumbled upon this :

   <<Do not use this GitHub action if you are in the following situations

     * Your code is built with Gradle: use the SonarQube plugin for Gradle during the 
build>>

https://github.com/SonarSource/sonarcloud-github-action#user-content-do-not-use-this-github-action-if-you-are-in-the-following-situations

So I think we should remove it from GH and rather use it with Gradle. Not sure 
about all that though...

Opinions ?

Jacques