ENH - Histogram Flag Array for GLOWS L1B

[maxinelasp]

Summary

The histogram flag array for GLOWS L1B is filled with placeholder values but should contain various flags for data quality. These are described in 12.3 of the algorithm document, and mostly consist of copying data from L1A up. The flags data variable is already created in the CDF file.

Requirements

The more specific the better.

• update _compute_histogram_flag_array() function in glows_l1b_data.py to add required flags
• Validate that the flags match the validation data (Maxine has script and data for this)
• Update tests as needed

Related tickets

#2537