Fix fdo#80338: Help pages for Calc Data Stats

This patch adds the help button on all dialogs of Calc Data Statistics.

Change-Id: Ic74493a4df1341ca08b50c03290a386232c977e9
Reviewed-on: https://gerrit.libreoffice.org/10704
Reviewed-by: Olivier Hallot <olivier.hallot@edx.srv.br>
Tested-by: Olivier Hallot <olivier.hallot@edx.srv.br>