Fix build

Otherwise, the build fails with the following error:

.../src/src/interface/Node_select.cpp:254:46: error: missing template arguments before ‘(’ token
  254 |             reassign_children_rec(*it, QFlags(Qt::Unchecked));
      |                                              ^

(at least on Debian with Qt 5.15.2)

approved this merge request

added 3 commits

• f22101af...76965ca7 - 2 commits from branch solverstack:master
• 67c901c2 - Fix build

Compare with previous version

enabled an automatic merge when the pipeline for 67c901c2 succeeds

assigned to @pswartva

requested review from @pswartva

requested review from @faverge and removed review request for @pswartva

merged

mentioned in commit df18a58d