Log Message:
py-html-sanitizer: updated to 1.6.1

1.6:
Fixed another edge case where a tag which is allowed to be empty was erroneously \ 
removed if it contained not only whitespace but also a <br> tag.

1.5:
Fixed a few edge whitespace normalization edge cases and a bug where removing an \ 
empty tag removed all whitespace.
Added black for automatically formatting the Python code.
By default, links with target="_blank" get an additional \ 
rel="noopener" attribute (Article by Mathias Bynens). If you're \ 
overriding the list of allowed attributes for anchor tags you must add rel to \ 
your list.