Usually, git comes with https URL, those changes above will give you access to the https URL, otherwise, you will receive an error message:
Unable to find remote helper for ‘https’
Next, let’s go to ISPConfig Panel, System -> Server Config.
In Jailkit chroot app sections, add: php git curl
In Jailkit chrooted applications, add: /usr/bin/php /usr/bin/git /usr/bin/curl /usr/lib/git-core
Last is Save the settings off course.
Great, you’re done everything. Now, to test that this is work or not, try to create dummy website, and create shell user using that dummy website. Everything should be fine, If not, well.. Google is your only choice to solve your problem.