template.md is included in the ToC

[Relequestual]

When running adr-log -i, the template is considered to be an ADR, and therefore included in the ToC of index.md.

This is not desierable, and template.md should be excluded.

I believe this is a result of "fallback to auto-numbering for ADRs without filename prefixes or frontmatter".

I'd considser this also not desierable.

Cloning this repo and running adr-log -h . in the docs/adr folder includes template.md.