Formatting over HTML comments crates newline between each comment

[jpmorris]

Describe the bug

context

<!-- Space: MyGroup -->
<!-- Parent: parent-->
<!-- Parent: subparent-->
<!-- Title: title-->

To support https://github.com/kovetskiy/mark to send my markdown to confluence

expectation

<!-- Space: MyGroup -->
<!-- Parent: parent-->
<!-- Parent: subparent-->
<!-- Title: title-->

bug

<!-- Space: MyGroup -->

<!-- Parent: parent-->

<!-- Parent: subparent-->

<!-- Title: title-->

Reproduce the bug

printf -- '<!-- test -->\n<!-- test2 -->' | pipx run mdformat -

List your environment

 % mdformat --version
mdformat 1.0.0

[fchastanet]

I have this problem too adding this comment before problematic line:
<!-- markdownlint-disable-next-line MD013 -->
mdformat adds an empty line between the comment and the problematic line making mardownlint to fail

I found this work around

<!-- markdownlint-disable MD013 -->

`(node:9) MaxListenersExceededWarning: Possible EventEmitter memory leak detected. 11 close listeners added to [TLSSocket].Use emitter.setMaxListeners() to increase limit`

<!-- markdownlint-restore -->