It's been a couple of days and I am seeing entries like this on GA. How can I avoid such entries beside analytics_test?
Many of these can be eliminated with a hostname filter.
Open up filters for your domain and add a 'custom' filter, that only includes hostnames with your domain in them. For standard websites, there are no circumstances under which this would filter normal traffic - as all of them are viewing your content on your domain.
Ah yes, the dreaded yet pervasive Referral Spam technique. Google Analytics tries to automatically remove referral spam, but doesn't catch all of it.
There isn't a good solution to this, currently.
Option 1 is to add the domain to an Exclude filter when you see it...OR...you can apply an .htaccess rule to ignore traffic from the referring hostname. This requires frequent maintenance, unfortunately.
Option 2 is to use an Include filter on your valid hostnames, but this won't work if the referral spam bot uses the measurement protocol or if it requests content from your site.
Here's a frequently updated article that mentions some different solutions, e.g. plugins and SaaS services: https://raventools.com/blog/stop-referrer-spam/
Google Analytics isn't the only product affected by this, btw.