Add possibility to clone git with history in PDSPrepare

[lorriborri]

Situation

PDSPrepare has two flags to clone and upload the git history but it can not be defined via the sechub configuration

Wanted

User should define if he wants the PDSPrepare to download git history, when secretScan is defined or not

Solution

1. Merge variables pds.prepare.git.history.wanted and pds.prepare.git.autoremove.gitfiles.beforeupload to one variable (pds.prepare.add.scm.histroy)
2. Add addScmHistory to the sechub configuration

      "remote" : {
        "location" : "https://path-to-my-git-exmaple/repository.git", 
        "type" : "git",
        "addScmHistory" : "true"
      }

3. Make PDSPrepare clone with history when secretscan and addScmHistory is set to true
4. Add Warning when addScmHistory true but no secretScan defined