Avoid maven error `Unknown lifecycle phase \"-\"` when the value of a define contains `-`.
Don't split and trim maven arguments. Expect they come in as a list, keep them as list.
This is a breaking change compared to the old Groovy implementation which relied on using a shell for calling maven.
As an example, consider this diff:
```diff
- goals: 'org.apache.maven.plugins:maven-help-plugin:3.1.0:evaluate',
- defines: "-Dexpression=$pomPathExpression -DforceStdout -q",
+ goals: ['org.apache.maven.plugins:maven-help-plugin:3.1.0:evaluate'],
+ defines: ["-Dexpression=$pomPathExpression", "-DforceStdout", "-q"],
```
Also establish mavenExecute() via new JenkinsMavenExecuteRule in Groovy Unit Tests.
Co-authored-by: Stephan Aßmus <stephan.assmus@sap.com>
Co-authored-by: Christopher Fenner <26137398+CCFenner@users.noreply.github.com>
