bpo-37628: Fix IDLE config sample sizes (GH-14958)


The boxes for the font and highlight samples are now constrained by the overall config dialog size.  They gain scrollbars when the when a large font size makes the samples too large for the box.
(cherry picked from commit 3221a63c69268a9362802371a616f49d522a5c4f)

Co-authored-by: Tal Einat <taleinat+github@gmail.com>
5 files changed