sonarqube: Switch from `sonar.login` to `sonar.token`

[ppxl]

Some scans still occur with the Sonar community branch plugin.

As it looks, at least for SonarQube 25.x, no longer supports these scans via '-Dsonar.loginJVM parameter. Instead the [docs mention](https://docs.sonarsource.com/sonarqube-server/2025.1/analyzing-source-code/scanners/sonarscanner-for-maven) a dedicated-Dsonar.token` parameter.

I tested this successfully in a Jenkins replay job for cloudogu/spring-petclinic for the master build:

excerpt from sonarqube.groovy

 mvn "${sonarMavenGoal} -Dsonar.host.url=${sonarHostUrl} -Dsonar.token=${sonarLogin} ${sonarExtraProps}"