Alignment with Commonalities r3.3 & ATP

[albertoramosmonagas]

Problem description

• Commonalities r3.3 introduces new changes that didn't appear in r3.2, which were the guidelines for PopulationDensityData r3.1.

• The Population Density ATP needs to be updated by adding geohash validation in scenarios 01 and 07, including the missing scenario @population_density_data_05_async_operation_not_completed_scenario, reorganizing scenarios by HTTP codes to align with other ATPs, correcting the parameter name from sinkCredentials to sinkCredential, and fixing various typos.

Expected action
Align specifications and test plans with the latest guidelines and Update the Population Density ATP with geohash checks, add the missing scenario, reorganize by HTTP codes, fix the sinkCredential parameter, and correct typos.

Additional context

Related PRs:

• Recommendation and examples to provide schema context in test definitions in Fall 25 Feature Files to provide schema context Commonalities#492
• Changed Mandatory Description for date-time string format and updated template files in Missing Mandatory Description for date-time in CAMARA_common.yaml Commonalities#497
• ErrorInfo scheme unification ErrorInfo scheme unification ErrorInfo scheme unification ErrorInfo scheme unification Commonalities#506