Add RTA trigger jobs to packaging confs for Additional Libraries

Add RTA trigger jobs to packaging confs, so that RTA tests are triggered automatically when ever new content is updated to online repos. Only for 6.1.x at this time.

tqtc-qtsdk:
open file: tqtc-qtsdk\packaging-tools\configurations\releases\release-addons-61x.ini

Look for the sections starting with 'task' e.g. [task.repository.linux.x64.linux_addon.qt3d.common]  add new option 'rta_key_list:' as the last option in a section and add the correct trigger job name as the value e.g. above section:

rta_key_list:    RTA_trigger_6.1_AddOn_Qt3D_linux

Push changes to git, reviewer Johanna or Antti Kokko