Break line when encountering <div> tag

[SilverRainZ]

<div> is block-level element by default, let it behaves like a <p> element.

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BTW, A block-level element always starts on a new line and ends on a new line, so the condition would be better to change from:

tag.eq_ignore_ascii_case(b"p") && is_tag_close

to:

tag.eq_ignore_ascii_case(b"p")

I’m not sure if there was any special consideration for doing this before, so I kept the condition unchanged in this PR.