Set up label based automated GDASApp ctests on Gaea C6 and Ursa.

[RussTreadon-NOAA]

Currently label based automated GDASApp ctest can be run on Hera, Hercules, and Orion. This issue is opened to extend this capability to Gaea C6 and Ursa.

The role.jedipara account is used on Hera. This account exists on Gaea C6 and Ursa. Thus, the approach used on Hera will be followed on Gaea C6 and Ursa.

[RussTreadon-NOAA]

@DavidNew-NOAA , @CoryMartin-NOAA , and @guillaumevernieres

Hera will eventually go away. We should at the very least port automated Hera label based GDASApp ctests to Ursa. We use Gaea C6 for GFS v17 retrospective parallels. As such, it would be good to stand up automated GDASApp ctests on Gaea C6.

[RussTreadon-NOAA]

20250926 update

Gaea C6 was upgraded this week. spack-stack needs to be reinstalled. Enabling label-based GDASApp CI on Gaea C6 is on hold until the Gaea C6 spack-stack is rebuilt, tested, and confirmed to be working as intended.

Label-based GDASApp CI on Ursa has been enabled using the role.jedipara account. GDASApp PR #1914 will apply the Ursa labels.