Remove junit-platform.properties

[knoobie]

Vaadin's testbench should not provide a junit-platform.properties.. otherwise customer can't provide their own properties reliable anymore.

Adding a custom junit-platform.properties to my applicaiton results in:

[main] INFO org.apache.maven.plugin.surefire.SurefirePlugin - 
[main] INFO org.apache.maven.plugin.surefire.SurefirePlugin - -------------------------------------------------------
[main] INFO org.apache.maven.plugin.surefire.SurefirePlugin -  T E S T S
[main] INFO org.apache.maven.plugin.surefire.SurefirePlugin - -------------------------------------------------------
Jun 21, 2024 4:03:48 PM org.junit.platform.launcher.core.LauncherConfigurationParameters loadClasspathResource
WARNING: Discovered 2 'junit-platform.properties' configuration files in the classpath; only the first will be used.
Jun 21, 2024 4:03:48 PM org.junit.platform.launcher.core.LauncherConfigurationParameters loadClasspathResource
WARNING: Discovered 2 'junit-platform.properties' configuration files in the classpath; only the first will be used.
Jun 21, 2024 4:03:48 PM org.junit.platform.launcher.core.LauncherConfigurationParameters loadClasspathResource
WARNING: Discovered 2 'junit-platform.properties' configuration files in the classpath; only the first will be used.

Spoiler: My configuration was not the first one ;)

Related to: junit-team/junit5#2794