fix: cleanup error reporting

src/main/scala/com/fulcrumgenomics/umi/CollectDuplexSeqMetrics.scala

@@ -306,18 +306,19 @@ class CollectDuplexSeqMetrics
   override def execute(): Unit = {
     // Build the iterator we'll use based on whether or not we're restricting to a set of intervals
     val in = SamSource(input)
-    val _filteredIterator = in.iterator.filter(r => r.paired && r.mapped && r.mateMapped && r.firstOfPair && !r.secondary && !r.supplementary)
+    val _filteredIterator = in
+      .iterator
+      .filter(r => r.paired && r.mapped && r.mateMapped && r.firstOfPair && !r.secondary && !r.supplementary)
       .bufferBetter
     // Ensure the records are not consensus records
     _filteredIterator.headOption.foreach {
-      r =>
-        def exceptionString = s"Input BAM file to CollectDuplexSeqMetrics ($input) appears to contain consensus reads." +
+      rec =>
+        def exceptionString = s"Input BAM file to CollectDuplexSeqMetrics ($input) appears to contain consensus sequences. " +
           "CollectDuplexSeqMetrics cannot run on consensus BAMs, and instead requires the UMI-grouped BAM generated " +
           "prior to consensus calling. The UMI-grouped BAM is the output of running GroupReadsByUmi." +
-          s"\nFirst record in $input has consensus tags present:\n${_filteredIterator.head}"
+          s"\nFirst record in $input has consensus SAM tags present:\n$rec"
 
-        if (Umis.isConsensusRead(r)) throw new IllegalArgumentException(exceptionString)
-        else r
+        if (Umis.isConsensusRead(rec)) throw new IllegalArgumentException(exceptionString)
     }
     val iterator = intervals match {
       case None       => _filteredIterator