Add API to modify rules during filter2dnr conversion
Background
We want to be able the generate rule IDs during the filter to DNR conversion process. See https://gitlab.com/eyeo/adblockplus/abc/webext-sdk/-/merge_requests/228/diffs#note_831977687 for some context.
We can make an API that allow mutating the rules as they are created.
What to change
Provide an API to pass a callback to be able to modify the rule, to, for example, generate a rule ID.
Edited by Hubert Figuière