fix: form label padding right, #1258

packages/semi-foundation/form/form.scss

@@ -92,6 +92,7 @@ $rating: #{$prefix}-rating;
         font-weight: $font-form_label-fontWeight;
         color: $color-form_label-text-default;
         margin-bottom: $spacing-form_label-marginBottom;
+        padding-right: $spacing-form_label-paddingRight;
         display: inline-block;
         vertical-align: middle;
         @include font-size-regular;

packages/semi-foundation/form/rtl.scss

@@ -33,6 +33,7 @@ $rating: #{$prefix}-rating;
     
         &-field-label {
             padding-right: 0;
+            padding-left: $spacing-form_label-paddingRight;
     
             &-with-extra {
                 .#{$field}-label-extra {

packages/semi-foundation/form/variables.scss

@@ -7,6 +7,7 @@ $spacing-form_field_group_vertical-paddingTop: $spacing-base-tight; // 垂直布
 $spacing-form_field_group_vertical-paddingBottom: $spacing-base-tight; // 垂直布局表单组底部内边距
 
 // form label
+$spacing-form_label-paddingRight: $spacing-base; // 表单项标签右侧边距（水平布局）
 $spacing-form_label-paddingTop: ($height-control-default - 20px) * 0.5; // 表单项标签顶部内边距（水平布局）
 $spacing-form_label-marginBottom: $spacing-extra-tight; // 表单项标签底部外边距
 $spacing-form_label_extra-marginLeft: $spacing-extra-tight; // 表单项标签额外信息左侧边距