Add "float: right|left" support for css. (#1208)

Co-authored-by: Sasha Sorokin <10401817+brawaru@users.noreply.github.com>

helpers/parse.js

@@ -25,6 +25,7 @@ export const configuredXss = new xss.FilterXSS({
     whiteList: {
       'image-rendering': /^pixelated$/,
       'text-align': /^center|left|right$/,
+      float: /^left|right$/,
     },
   },
   onIgnoreTagAttr: (tag, name, value) => {