fix(component): flex setting-modal header & footer (#4818)

packages/frontend/component/src/components/setting-components/share.css.ts

@@ -1,8 +1,8 @@
 import { globalStyle, style } from '@vanilla-extract/css';
 
 export const settingHeader = style({
-  height: '68px',
   borderBottom: '1px solid var(--affine-border-color)',
+  paddingBottom: '24px',
   marginBottom: '24px',
 });