Update readme with requirement on maven 3.9.0+
Trying to build main branch locally with maven 3.8.7 I got :
[ERROR] Failed to execute goal org.eclipse.tycho:tycho-source-plugin:4.0.9:plugin-source (plugin-source) on project org.eclipse.team.svn.target: The plugin org.eclipse.tycho:tycho-source-plugin:4.0.9 requires Maven version 3.9.0 -> [Help 1]
[ERROR]
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR]
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/PluginIncompatibleExceptionWe should update the readme accordingly
Edited by Clément Honoré