[Refactor][Nice to have] rename timeStamp to streamTimeStamp or move to StreamUrlIdHandler

Its quit confusing if you want to implement a service getTimeStamp is in the context of the StreamExtractor and not the upload date or something like this. It would be better to move this to the StreamUrlIdHandler because its a url parsing part and not something that is in the meta data of the stream, like the most data that is can be accessed over the StreamExtractor

++ extractor/src/main/java/org/schabi/newpipe/extractor/stream/StreamUrlIdHandler.java

public interface StreamUrlIdHandler extends UrlIdHandler {
String getTimeStamp(String url) throws ParsingException;
}

or directly in the living standard implementation of url parsing that comes with DTube and MediaCCC support. (Url Parsing get maybe moved to a whole new project)

Relevent for new implementations.
And currently in the DTube Implementation (already fixed local):
Wrong Implementation
|_ Usage of Wrong Implementation
|_ Base Needs to be removed
|_ Base Needs to be removed now

Review StreamExtractor.java and StreamUrlIdHandler.java to determine where getTimeStamp belongs, then inspect the referenced DTubeStreamExtractor.java and DTubeParsingHelper.java usages. Compare the rename and relocation options before choosing a consistent API boundary. Done means the timestamp responsibility and naming are consistent across the affected interfaces and DTube implementation.