Fix: Do not regenerate global scenario config if global scenario config is a symlink

The following discussion from !90 (merged) should be addressed:

• @kartmann started a discussion:

  Seems to work well so far.

  One issue still, though: When using a symlink for the global scenario config (global.cfg), the name of the scenario is part of the config file and is regenerated when viewed, leading to changes such as:

  -# Global Config from Scenario armar7_l1_1_low_level_components
  +# Global Config from Scenario armar7_l1_1_low_level_components_sim

  It would be good if a global scenario config would also not be updated if it is a symlink