Support text/html ContentType for attachments

[Oleksandr Shevtsov]

I found this implementation for an axe pytest integration that uses content type of HTML to render the page (Allure Framework docs) within the report. Of the content types offered for cypress-allure-plugin, text/css is compatible with .html but will only allow for a html file to be downloaded, not rendered.
Is there a way to add text/html as a ContentType?
Or is there already a solution to this that I am overlooking?

Originally posted by @robi4513 in #136

[Oleksandr Shevtsov]

Released in v2.32.1