Feature/13 move build scripts and bind mount

[alee-ntap]

What this PR does / why we need it:

Which issue(s) this PR fixes:
Fixes #13

Special notes for your reviewer:

There is another -test branch for test this PR that specified branch for action/checkout that contains all these changes. Tested workflow with changes in this PR utilized by package-htop:
https://github.com/gardenlinux/package-htop/actions/runs/6941494228

Release note:
NONE

[gardener-robot]

@alee-ntap Thank you for your contribution.

[alee-ntap]

After discussion, it has been decided to retain the inclusion of the build_* scripts within the container images to support local builds. Therefore, I will proceed with updating the current PR to reflect this decision.

To ensure that the workflow can be properly tested in the development branch, we still require the use of a bind mount when bringing up the container. However, this bind mount should only be applied within the workflow.

Considering that the build_* scripts are already available under /usr/local/bin within the container images, we need to bind mount this directory to /usr/local/sbin. This will enable the possibility of workflow development tests while the necessary scripts available inside the container in the workflow.

By making these adjustments, we can support both local builds by keeping the build_* scripts inside the container images, and also support workflow development and testing in the development branch.

[nanory]

LGTM