Fix test reference mismatch

[apchoiCMD]

What this PR fixed

• Two new ioda converters that work with mktime in a C library function that need to ensure consistent behavior across different machines with different time zones (e.g., Orion (CST) and Hera (UTC))
• Set the time zone explicitly using the tzset function with UTC time zone
• Used oops/utils to make dateime to Julian date so now code is a lot simpler than before

Fixed #783

[guillaumevernieres]

I don't think changing the environment is a safe thing to do, you're assuming TZ isn't used anywhere else.

[guillaumevernieres]

Have a look here @apchoiCMD :
https://github.com/JCSDA/ioda/blob/develop/src/core/IodaUtils.h

[guillaumevernieres]

Thanks @apchoiCMD . Looks good, just a few minor comments. Did you check that the datetime is still correct?

[apchoiCMD]

Thanks @apchoiCMD . Looks good, just a few minor comments. Did you check that the datetime is still correct?

Yes, I have checked min & max output by using online tools (UTC) compared to original netcdf data, too! Everything was ok!

[AndrewEichmann-NOAA]

Aside from the filtering of obs with bad dates, looks good

[guillaumevernieres]

Looks good. Thanks @apchoiCMD .

[ShastriPaturi]

Approving based on others comments

[emcbot]

Automated Global-Workflow GDASApp Testing Results:
Machine: hera

Start: Tue Dec 19 20:35:00 UTC 2023 on hfe07
---------------------------------------------------
Build:                                 *SUCCESS*
Build: Completed at Tue Dec 19 21:29:29 UTC 2023
---------------------------------------------------
Tests:                                  *Failed*
Tests: Failed at Tue Dec 19 21:47:46 UTC 2023
Tests: 87% tests passed, 7 tests failed out of 55
	1701 - test_gdasapp_soca_JGDAS_GLOBAL_OCEAN_ANALYSIS_RUN (Failed)
	1703 - test_gdasapp_soca_JGDAS_GLOBAL_OCEAN_ANALYSIS_CHKPT (Failed)
	1704 - test_gdasapp_soca_JGDAS_GLOBAL_OCEAN_ANALYSIS_POST (Failed)
	1705 - test_gdasapp_soca_JGDAS_GLOBAL_OCEAN_ANALYSIS_VRFY (Failed)
	1707 - test_gdasapp_soca_incr_handler (Failed)
	1719 - test_gdasapp_atm_jjob_var_run (Failed)
	1720 - test_gdasapp_atm_jjob_var_final (Failed)
Tests: see output at /scratch1/NCEPDEV/da/Cory.R.Martin/CI/GDASApp/workflow/PR/786/global-workflow/sorc/gdas.cd/build/log.ctest