Turn on CI checking of indentation

[s-good]

Description

The lines in cpplint.py that check indentation were commented out so this wasn't being checked in the CI. This PR uncomments those lines and fixes the resulting errors.

Impact

None.

Checklist

• I have updated the unit tests to cover the change
• New functions are documented briefly via Doxygen comments in the code
• I have linted my code using cpplint
• I have run the unit tests
• I have run mo-bundle to check integration with the rest of JEDI and run the unit tests under all environments: http://fcm1/cylc-review/taskjobs/hadgs/?suite=orca_jedi_indent

[twsearle]

looks good.