vAPI.tabs.executeScript() can't throw

Related commit:
- aed850978e

No need to mind rejected promise after all,
vAPI.tabs.executeScript() is designed to
not fail -- I had forgotten about this.

src/js/start.js

@@ -77,7 +77,6 @@ const initializeTabs = async function() {
             toCheck.push(
                 /^https?:\/\//.test(url)
                     ? vAPI.tabs.executeScript(id, checker) 
-                               .then(result => result, ( ) => false) 
                     : false
             );
             tabIds.push(id);