Merge branch 'hotfix/#6302-fix-#4747-file-generator-properly-generates-files'

Close #6302
Close #4747
Add failing test to Number element
Fix invalid use of Float validator in favor of Regex validator
Additionally test and allow for negative values in Regex pattern
Fix stupidly slipped in character... this can really only happen ony german keyboard layout
Merge branch 'hotfix/#6326-thousand-separator-in-number-validator' into develop

Forward port #6326