fix(iOS): fix faux-sticky button placement (#715)

hopefully the final fix for #667 to make it actually work

routes/_components/compose/ComposeStickyButton.html

@@ -119,7 +119,6 @@
           document.body.appendChild(element)
           let rect = this.refs.wrapper.getBoundingClientRect()
           Object.assign(element.style, {
-            right: `${rect.right}px`,
             left: `${rect.left}px`,
             position: 'fixed'
           })