Fix variable passthrough in SAST template when using DinD

What does this MR do?

After the introduction of !24108 (merged), variables can't be passed through to the docker run, because of two things happening at the same time:

1. Variable expansion in sh - ENVS=".." docker run $ENVS will expand $ENVS in docker run to empty before it evaluates them at the beginning of the line
2. $ENVS passed as literal to docker through quotes, when we want docker run to interpret them as variables to pass.

The solution is to move it into a separate step and removing the quotes, like in this MR.

See the change in action and succeeding job.

Does this MR meet the acceptance criteria?

Conformity

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Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
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