Github Action fix for newer build version ,make release tag configurable as action input & checkout build branch directly

[pykpkg47]

Description

• fix for newer build version: the Action failed to start on newer build versions because these included a broken symlink
  which prevents it to start [issue for github action] (When action repository contains a broken symbolic link, "Set up job" stage will fail actions/runner#3234) remove of the broken
  symlink fixed it.
• added a action input for the release tag , if the input is empty it will use the armbian version as release tag like before
• checkout the selected (default main) branch of armbian build directly which can prevent failed runs if a change broke
  cloning of the main repo [like this one] (feat: add ST7796 kernel module (fbtft) #7543 (comment))

How Has This Been Tested?

manual run of the modufied action: https://github.com/pykpkg47/armbian-image-build/actions/runs/12303042333
release with custom tag :https://github.com/pykpkg47/armbian-image-build/releases/tag/test_tag_pr

Checklist:

• [x ] My code follows the style guidelines of this project
• [x ] I have performed a self-review of my own code
• [x ] I have commented my code, particularly in hard-to-understand areas
• [x ] My changes generate no new warnings
• [x ] Any dependent changes have been merged and published in downstream modules