fix: button lineheight

Author: undefined

components/button/style/index.less

@@ -20,7 +20,7 @@
   // Fixing https://github.com/ant-design/ant-design/issues/13214
   // It is a render problem of chrome, which is only happened in the codesandbox demo
   // 0.001px solution works and I don't why
-  line-height: @line-height-base - 0.001;
+  line-height: @line-height-base;
   .btn;
   .btn-default;