Add "What's new" user note for ttc font support

sauerburger · sauerburger · commit 1220c51ef2da · 2022-06-20T11:28:24.000+02:00
diff --git a/doc/users/next_whats_new/ttc_font_support.rst b/doc/users/next_whats_new/ttc_font_support.rst
@@ -0,0 +1,7 @@
+TTC font collection support
+---------------------------
+
+Fonts in a TrueType collection file (TTC) can now be added and used. Internally,
+the embedded TTF fonts are extracted and stored in the matplotlib cache
+directory. Users upgrading to this version need to rebuild the font cache for
+this feature to become effective.
