Do not document unit tests validating tests

What it does

Skip unit test documentation

Do no document unit tests validating helpers used in the tests. Only the unit tests folder is documented.

In details

• If a test mark is category("unit-tests"), the documentation code does not associate a mark with the code
• When a test has no mark, it is not documented

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Tests

Tested locally with uv run sylva-test-framework gen-doc

The result is the following one

## `test_gitops.py`

### `test_vault_config_custom_resources`

Assuming that

- the Vault unit is enabled in the management cluster values
- there exists a team with vault_write_group defined in the management cluster values
- the related Keycloak group has a user defined in the management cluster values

This test ensures that the related custom resources deployed by the vault config operator exist and that their status is correct.

**Marks:** category(default), category(gitops), cluster(management)

### `test_keycloak_config_custom_resources`

Assuming that

- the Keycloak unit is enabled in the management cluster values
- there exists a team with vault_write_group defined in the management cluster values
- the related Keycloak group has a user defined in the management cluster values

This test ensures the existence and the correct status of

- The custom resources deployed by the keycloak operator
- Related resources such as the initial password secret of the gitops user

**Marks:** category(default), category(gitops), cluster(management)

## `test_gitops_unit_tests.py`

Unit tests for helper functions.

This test file focuses on unit testing the functions used in test_gitops.py

## `test_health_checks.py`

### `test_node_conditions`
...