I have a MacBook Pro 2017 running MacOs High Sierra Version 10.13.6. When i download the Sourcetree 2.7.6a zip file from SourceTree site and unzip it, I get a .app file. I double-clicked on the file and it says cannot open this file. I tried copying the file to Applications and then clicked in it, it gave me the same issue. I also tried to restart the system and check, it gave me the same issue. The only version that i am able to run on my machine is version 2.1 because its installation file was a .dmg file. Need help to troubleshoot this issue.