[lldb] Limit formatter-section extractor range (#140139)
The formatter extraction would look at too much data for one type -
possibly reading data outside the section.
This PR limits the size of the `DataExtractor` to the one specified in
the record size before - previously, the whole section was looked at.
Similarly, `ForEachFormatterInModule` skipped zero-bytes but didn't stop
when reaching the end of the extractor.
I added a test for both cases.
