feat: sidesheet add tokens

packages/semi-foundation/sideSheet/sideSheet.scss

@@ -76,6 +76,7 @@ $module: #{$prefix}-sidesheet;
         margin: $spacing-sideSheet_title-margin;
         @include font-size-header-5;
         font-weight: $font-sideSheet_title-fontWeight;
+        font-size: $font-sideSheet_title-text-size;
         color: $color-sideSheet_main-text;
         text-align: left;
     }

packages/semi-foundation/sideSheet/variables.scss

@@ -14,3 +14,4 @@ $spacing-sideSheet_footer-padding: $spacing-loose; // 侧边栏 footer 内边距
 
 // Font
 $font-sideSheet_title-fontWeight: $font-weight-bold; // 侧边栏标题文本字重
+$font-sideSheet_title-text-size: $font-size-header-5; // 侧边栏标题文本字号