fix(datasource): allow literal in set_sensitive

[billf]

Rollback Plan

If a change needs to be reverted, we will publish an updated version of the library.

Changes to Security Controls

None.

Description

Permit literal values in set_sensitive for helm_release data source.
The schema already allowed this, but the implementation did not handle it.

Acceptance tests

• Have you added an acceptance test for the functionality being added?

Release Note

Release note for CHANGELOG:

`datasource/helm_release`: Implemented `set_sensitive` with literal type

References

#1615

Community Note

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