[Tests] Fix: Accept uppercase calibration type

Description

Triggering this pipeline failed because I gave an uppercase value for the CALIBRATION variable. This led to and error: __main__.py: error: argument --calibration: invalid choice: 'DARK' (choose from 'correct', 'dark', 'all').

I have added this fix to accept uppercase values and compare it against the lowercase choices.

How Has This Been Tested?

Rebased onto fix/lpd-dark-daemon-children and will run the test with the same failed variables' values.

Relevant Documents (optional)

Types of changes

• Bug fix (non-breaking change which fixes an issue)

Checklist:

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