[CircleCi] updatebuild script: merge with upstream branch

[wilzbach]

I just realized that for #4921 the style check fixes aren't included. In general it makes a lot of sense to merge to merge with the upstream branch, s.t. changes are always tested as they would be merged (@CyberShadow's DAutoTest behaves similarly). While I was at the file I did a few tiny improvements:

• provide default value for CIRCLE_NODE_INDEX (makes the script easier to run
  manually)
• move setup_repos before style task, s.t. the latest style requirements
  are enforced
• removed exclusion of failing modules for the individual module
  coverage tests (this is due to @schveiguy's & @MartinNowak's work on issue 16291. Thanks!)

CC @MartinNowak

[MartinNowak]

That merge is the other way round, master into PR, does that matter?

[wilzbach]

That merge is the other way round, master into PR, does that matter?

It shouldn't, but to be safe, I reverted the order, s.t. we now really merge the PR into the the target branch.

[wilzbach]

So we currently get failures with CircleCi due to this:

This has to do with the new public unittest tester: to avoid random failures a specific git version of the tools repo is checked out.
The problem is that we do a git clone with --depth 1 by default and just recently a new commit got into the tools repo, s.t. the checked out version isn't fetched anymore due.

-> I have added a fix to this PR and raised the priority - would be nice to get this in.

Note that this touches solely the circle.sh files and with the status quo of CircleCi being broken, it's definitely an improvement ;-)