fix: Add QNAME in pair identification

Author: DenisVerkhoturov

src/main/java/htsjdk/samtools/SAMRecord.java

@@ -338,6 +338,7 @@ private boolean hasReferenceName() {
      */
     public boolean isPair(final SAMRecord record) {
         return record != null
+                && Objects.equals(this.getReadName(), record.getReadName())
                 && this.getMateAlignmentStart() == record.getAlignmentStart()
                 && record.getMateAlignmentStart() == this.getAlignmentStart()
                 && !NO_ALIGNMENT_REFERENCE_NAME.equals(this.getMateReferenceName())

src/test/java/htsjdk/samtools/SAMRecordUnitTest.java

@@ -1124,9 +1124,11 @@ public void testRecordsArePairIfTheyLinkEachOtherInMateFields() {
     @Test
     public void testRecordsArePairIfTheyHaveNoMateFields() {
         final SAMRecord first = new SAMRecord(new SAMFileHeader(new SAMSequenceDictionary()));
+        first.setReadName("example1");
         first.setAlignmentStart(42);
         first.setReferenceName("chrm1");
         final SAMRecord second = new SAMRecord(new SAMFileHeader(new SAMSequenceDictionary()));
+        first.setReadName("example1");
         second.setAlignmentStart(142);
         second.setReferenceName("chrm2");