Removing curly brackets when using percentencode

I’m trying to get a datalink in one of my colums in a table. I know the link needs to be percentencoded, but I have a problem. The part I want percentencoded is stored in a variable; therefore by my understanding, in a list.
i.e: job_name = {‘latest/nightly/test-fw-nrfconnect-ble’}
The problem is that when I use ${job_name:percentencode}, the curlybrackets : { and }, gets encoded aswell. Therefore the strings %7B and %7D gets appended to the start and end, which makes the url invalid.
I principle, if there was a way to do something like this (${job_name:raw:percentencode}), that would fix it.
Any ideas?

Also, is there a way to instead use queries in the datalink, so that it gets data from the same row?