Extra space after a closing emphasis mark

```
$ echo 'hello'{\,,\",:,\[,.,\!,\?}'
' | html2text
_hello_ ,
_hello_ "
_hello_ :
_hello_[
_hello_.
_hello_!
_hello_?

```
Note in the first three lines of the output, there is an extra space after the closing `_` emphasis mark.

This is a bug, because Markdown has no problem with a punctuation immediately following the closing emphasis mark:
```
$ echo _hello_{\,,\",:,\[,.,\!,\?} | markdown

hello, hello“ hello: hello[ hello. hello! hello?

```
The same rendered by GitHub: _hello_, _hello_" _hello_: _hello_[ _hello_. _hello_! _hello_?

I guess the extra space is added here:

https://github.com/Alir3z4/html2text/blob/099c4b8bfeea09d640e18324bb1d44f051371940/html2text/__init__.py#L295-L297

Or here, which explains why the bottom four results don't have the extra space:

https://github.com/Alir3z4/html2text/blob/099c4b8bfeea09d640e18324bb1d44f051371940/html2text/__init__.py#L860-L868