Build the twitter:site / twitter:creator meta-tag block. Returns
an empty string when neither handle is configured so the caller can
safely interpolate the result without producing empty meta tags.
Returns string
Newline-joined meta tags (no trailing newline) or ''
Build the
twitter:site/twitter:creatormeta-tag block. Returns an empty string when neither handle is configured so the caller can safely interpolate the result without producing empty meta tags.