Ability to place value between matched regex groups

[kylepeeler]

Hi there,

Our team requires us to prefix all commits with (replacing our internal tool with fkapp for this example): fkapp://2939392838.

In this case, I usually name my branches kpeeler/fkapp2939392838/briefDescriptionOfFeature.

I was able to figure out how to prefix the commit by the middle part of the commit message using the following regex:

(fkapp)(\d+) which results in the prefix fkapp2939392838... but I need it to be fkapp://2939392838. How can I achieve this?