fix: don't show empty items in Space component (#26721)

components/space/style/index.less

@@ -2,6 +2,7 @@
 @import '../../style/mixins/index';
 
 @space-prefix-cls: ~'@{ant-prefix}-space';
+@space-item-prefix-cls: ~'@{ant-prefix}-space-item';
 
 .@{space-prefix-cls} {
   display: inline-flex;
@@ -25,4 +26,10 @@
   }
 }
 
+.@{space-item-prefix-cls} {
+  &:empty {
+    display: none;
+  }
+}
+
 @import './rtl';