Update-MarkdownHelp adds and removes blank lines

[BernieWhite]

Steps to reproduce

• In an existing cmdlet markdown document add a blank line between ## DESCRIPTION and first line of the description text. e.g.

## DESCRIPTION

Create markdown from an input object.

## EXAMPLES

• With no defined related links, create a single blank directly after the ## RELATED LINKS section.

## NOTES

## RELATED LINKS

Expected behavior

• A single blank line created after section headers such as description should be preserved for readability.
• Multiple sequential blank lines after section headers should be removed/reduced down to one.
• Blank line should not be added to after section header if it didn't exist before Update-MarkdownHelp was called.
• No more then a single blank line should be created after the related links section with no related links have been defined.

Actual behavior

• Blank line is removed.

## DESCRIPTION
Create markdown from an input object.

## EXAMPLES

• Blank line is added.

## NOTES

# RELATED LINKS

Environment data

v0.8.3

[vors]

Yeah, it would be great to preserve blanks. I fixed a countless number of bugs with blank lines and as far as Update-MarkdownHelp is noop second time, I'm pretty happy. Feel free to poke around in this codepath.