Section component uses incorrect color variable

[zhelezkov]

Hey!
I noticed that Section component uses --tgui--bg_color, but in my understanding it should use --tgui--section_bg_color variable. otherwise there's some inconsistency comparing to tg theme
https://github.com/Telegram-Mini-Apps/TelegramUI/blob/main/src/components/Blocks/Section/Section.module.css#L3

[wishyoudie]

Fixed in #53. Waiting for maintainers to approve.

[zhelezkov]

amazing! thanks a lot for a quick response