BUG - GLOWS L2 histogram_flag_array should be an integer

[sdhoyt]

Description of the issue

The GLOWS L2 YAML file defines the histogram_flag_array variable FORMAT as I2, but it is being stored as a CDF_DOUBLE. The code needs to be updated to set the data type to an integer when stored in the xarray DataArray.

Steps to reproduce the issue

I created the file where this issue was found using the following CLI command:

IMAP_API_KEY=<prod api key> imap_cli --instrument glows --data-level l2 --descriptor hist --start-date 20260128 --version v003 --dependency imap_glows_l2_hist-c499397b_20260128-repoint00140_v003.json  --repointing repoint00140

Expected vs Actual behavior

histogram_flag_array is type double, but should be stored as type int

Additional notes, affected areas, and suggested fixes

Similar to #2807 and #2810