Google recommends not to delete the HTTP page from the Google Search Console
Recently, Google representative John Mueller reminded that if you delete the HTTP version of the page using the appropriate tool in the Google Search Console all other variants of the URL will also be deleted. Therefore, doing so is not recommended. John Mueller noted:
If you remove the HTTP version in webmaster tools other versions will be removed as well (HTTPS, with www prefix or without it). It's definitely not what you want. Sending a request for removal/deindexation separate poor URL would be the best option
In January, Google Chrome has started to warn about insecure HTTP pages. And this month, according to Mozcast, the share of HTTPS websites in top 10 Google reached 45%.