Wrong is_freshness_enabled on stg_sources when warn_after is missing

[cos-pet-learn]

Describe the bug

Sources are flaged with is_freshness_enabled = false when warn_after is not configured, but error_after is configured

Steps to reproduce

I have configured freshness at source level:

version: 2

sources:
  - name: sdqn
    freshness:
      error_after:
        count: 168
        period: hour

Expected results

is_freshness_enabled = true in stg_sources for all tables in that source

Actual results

is_freshness_enabled = false in stg_sources for all tables in that source

Screenshots and log output

System information

The contents of your packages.yml file:

packages:
  - package: dbt-labs/dbt_utils
    version: ">=1.3.0"
  - package: dbt-labs/audit_helper
    version: ">=0.6.0"
  - package: dbt-labs/codegen # https://github.com/dbt-labs/dbt-codegen
    version: 0.12.1
  - package: Snowflake-Labs/dbt_constraints
    version: ">=1.0.0"
  - package: get-select/dbt_snowflake_query_tags
    version: [">=2.0.0", "<3.0.0"]
  - package: get-select/dbt_snowflake_monitoring
    version: ">=5.3.1"
  - package: entechlog/dbt_snow_mask
    version: ">=0.2.4"
  - package: dbt-labs/dbt_project_evaluator
    version: ">=0.14.0"

Which database are you using dbt with?

• postgres
• redshift
• bigquery
• snowflake
• trino/starburst
• other (specify: ____________)

The output of dbt --version:

versionless
15:46:31 No such option: --project-dir

Additional context

Are you interested in contributing the fix?