[MNG-7098] Keep the project counter intact when resuming a multi-module project.

[MartinKanters]

This code change was accidentally already merged into master, and then reverted. This is the original PR.

---

This PR ensures that when a multi module project is resumed halfway, the project progress counter is not reset.
Related issue.

Following this checklist to help us incorporate your
contribution quickly and easily:

• Make sure there is a JIRA issue filed
  for the change (usually before you start working on it). Trivial changes like typos do not
  require a JIRA issue. Your pull request should address just this issue, without
  pulling in other changes.
• Each commit in the pull request should have a meaningful subject line and body.
• Format the pull request title like [MNG-XXX] SUMMARY, where you replace MNG-XXX
  and SUMMARY with the appropriate JIRA issue. Best practice is to use the JIRA issue
  title in the pull request title and in the first line of the commit message.
• Write a pull request description that is detailed enough to understand what the pull request does, how, and why.
• Run mvn clean verify to make sure basic checks pass. A more thorough check will
  be performed on your pull request automatically.
• You have run the Core IT successfully.

If your pull request is about ~20 lines of code you don't need to sign an
Individual Contributor License Agreement if you are unsure
please ask on the developers list.

To make clear that you license your contribution under
the Apache License Version 2.0, January 2004
you have to acknowledge this by using the following check-box.

• I hereby declare this contribution to be licenced under the Apache License Version 2.0, January 2004

• In any other case, please file an Apache Individual Contributor License Agreement.

[michael-o]

Will schedule for the next couple of days

[MartinKanters]

Thanks for the review and merge @gnodet and @michael-o !