Make tab height uniform across floaters and panels

indra/newview/skins/default/xui/en/floater_about.xml

indra/newview/skins/default/xui/en/floater_blocked.xml

indra/newview/skins/default/xui/en/floater_profile.xml

...a/newview/skins/default/xui/en/floater_rlv_behaviours.xml

indra/newview/skins/default/xui/en/floater_tools.xml

indra/newview/skins/default/xui/en/panel_group_roles.xml

indra/newview/skins/default/xui/en/panel_main_inventory.xml

...wview/skins/default/xui/en/panel_marketplace_listings.xml

.../newview/skins/default/xui/en/panel_outfits_inventory.xml

indra/newview/skins/default/xui/en/panel_people.xml

indra/newview/skins/default/xui/en/panel_places.xml

indra/newview/skins/default/xui/en/panel_region_access.xml

.../newview/skins/default/xui/en/panel_script_ed_preproc.xml

.../newview/skins/default/xui/en/panel_snapshot_postcard.xml

indra/newview/skins/default/xui/en/widgets/tab_container.xml