Specifying :all on a package with no sub rules will emit incorrect things

[olivermt]

Code of Conduct

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Versions

Newest of all relevant packages

Operating system

macos

Current Behavior

mix usage_rules.sync ash.md ash:all will produce:

<!-- usage-rules-start -->
<!-- usage-rules-header -->
# Usage Rules

**IMPORTANT**: Consult these usage rules early and often when working with the packages listed below. 
Before attempting to use any of these packages or to discover if you should use them, review their 
usage rules to understand the correct patterns, conventions, and best practices.
<!-- usage-rules-header-end -->


<!-- usage-rules-end -->

Reproduction

No response

Expected Behavior

No response

[zachdaniel]

@olivermt mind putting Claude to work on this 😆

[olivermt]

Yeah I will fix it since I have the repro open 😆