RegExp patterns for dynamicAttributes

[yhatt]

Is your feature request related to a problem? Please describe.
When creating Web apps, I often use data attribute to pass the value generated from server to JS through HTML. For keeping critical styles that are depending on attribute values, I have thought it is useful to make a solution to mark a bunch of attributes that have the same rule, as "dynamic".

Describe the solution you'd like
Allow RegExp patterns in dynamicAttributes, such as [/^data-.+/].

Describe alternatives you've considered
safelist: It works well enough to keep selectors for dynamic attributes. However, sometimes need to want more fine tuning. (e.g. purge styles for the custom element such as <data-table> provided by a framework, and keep user styles for data- attribute)

Additional context
Currently dynamicAttributes just ignores RegExp. If it was supported, the consistency of PurgeCSS configuration would be improved too.

Another useful case of RegExp pattern is /^.+$/. It can treat all attribute selectors as dynamic, and protect from unexpected purging.