BUG: `test_load_w_pad` failures

[jklenzing]

Description

For pysat 3.2.0, the new test_load_w_pad test fails for some instruments.

To Reproduce this bug:

run pytest with pysat develop

Test configuration

• OS: Ventura
• Version: Python 3.10.9
• pysat develop

Additional context

• cnofs_plp
• icon_euv
• maven_insitu_kp
• maven_sep
• timed_guvi, tag='sdr-imaging' (all inst_ids) with combine_times=True

[jklenzing]

maven_sep succeeds with xarray 2024.3.0, but fails with 2024.6.0