Add a function to create COM-like paths under DATAROOT

[DavidHuber-NOAA]

Description

This adds the dataroot_com_path function to bash_utils.sh to create a COM-like path in DATAROOT space.
Resolves #4474

Type of change

• Bug fix (fixes something broken)
• New feature (adds functionality)
• Maintenance (code refactor, clean-up, new CI test, etc.)

Change characteristics

• Is this change expected to change outputs NO
• Is this a breaking change (a change in existing functionality)? NO
• Does this change require a documentation update? NO
• Does this change require an update to any of the following submodules? NO

How has this been tested?

Tested at the command line on C6:

> . bash_utils.sh
> ROTDIR=/gpfs/f6/drsa-hurr1/world-shared/David.Huber/rt_metp/COMROOT/C96C48_hybatmDA_metp
> DATAROOT=/gpfs/f6/drsa-precip4/world-shared/David.Huber/RUNDIRS/C96C48_hybatmDA_metp
> dataroot_com_path ${ROTDIR}/gfs.20211229
/gpfs/f6/drsa-precip4/world-shared/David.Huber/RUNDIRS/C96C48_hybatmDA_metp/gfs.20211229

Checklist

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have documented my code, including function, input, and output descriptions
• My changes generate no new warnings
• New and existing tests pass with my changes
• This change is covered by an existing CI test or a new one has been added
  - Not yet. A future PR will use this in CI tests.
• Any new scripts have been added to the .github/CODEOWNERS file with owners

[aerorahul]

Looks good. Just one suggestion to disable tracing inside the function.

[DavidHuber-NOAA]

@aerorahul I have retested this:

> COMROOT=/gpfs/f6/drsa-hurr1/world-shared/David.Huber/rt_gsidiags/COMROOT
> DATAROOT=/gpfs/f6/drsa-precip4/world-shared/David.Huber/RUNDIRS/C96C48_hybatmDA_gsidiags/gdas.2021122100
> COMOUT_ATMOS_ANALYSIS=/gpfs/f6/drsa-hurr1/world-shared/David.Huber/rt_gsidiags/COMROOT/C96C48_hybatmDA_gsidiags/gdas.20211221/00//analysis/atmos
> dataroot_com_path ${COMOUT_ATMOS_ANALYSIS}
/gpfs/f6/drsa-precip4/world-shared/David.Huber/RUNDIRS/C96C48_hybatmDA_gsidiags/gdas.2021122100/C96C48_hybatmDA_gsidiags/gdas.20211221/00/analysis/atmos

It gets a little redundant/deep into the DATAROOT, but in operations this would look something like

> COMROOT=/lfs/h1/ops/prod/com
> DATAROOT=/lfs/f1/tmp
> COMOUT_ATMOS_ANALYSIS=/lfs/h1/ops/prod/com/gfs/v17/gdas.20211221/00/analysis/atmos
> dataroot_com_path ${COMOUT_ATMOS_ANALYSIS}
/lfs/f1/tmp/gfs/v17.0/gdas.20211221/00/analysis/atmos

which is the desired outcome.

[aerorahul]

lgtm