Fix sniffing of readname sorted BAM files

This fixes https://github.com/galaxyproject/galaxy/issues/6949.
The problem is that `super` would fall back to the BamInputSorted
sniffer, which prevents sniffing. Includes a test file for the new
datatype upload testing framework.

lib/galaxy/datatypes/binary.py

@@ -556,7 +556,7 @@ class BamQuerynameSorted(BamInputSorted):
     file_ext = "qname_sorted.bam"
 
     def sniff(self, file_name):
-        return super(BamQuerynameSorted, self).sniff(file_name) and not self.dataset_content_needs_grooming(file_name)
+        return BamNative().sniff(file_name) and not self.dataset_content_needs_grooming(file_name)
 
     def dataset_content_needs_grooming(self, file_name):
         """