Lint does not pick missing hash curly braces in epp arguments

[yvf]

Describe the Bug

In the below code, the enclosing {} are missing. Puppet parses it without error (and it works !) but AFAICS this is totally undocumented behavior, and is rather confusing. I think this should be a lint error or warning.

class test_epp_hash {
  file {
    'test.file':
      content => epp('template.epp',
        'key' => 'value',
      );
  }
}

Expected Behavior

Should raise a lint error or warning.

Steps to Reproduce

Environment

• Version 4.2.4
• Platform RHEL8

Additional Context