BUmp Kraken2 nf-core module to prevent huge logs

modules.json

@@ -103,7 +103,7 @@
                     },
                     "kraken2/kraken2": {
                         "branch": "master",
-                        "git_sha": "c8e35eb2055c099720a75538d1b8adb3fb5a464c",
+                        "git_sha": "7c695e0147df1157413e06246d9b0094617d3e6b",
                         "installed_by": ["modules"]
                     },
                     "krakentools/combinekreports": {

modules/nf-core/kraken2/kraken2/main.nf

@@ -31,7 +31,7 @@ process KRAKEN2_KRAKEN2 {
     def unclassified = meta.single_end ? "${prefix}.unclassified.fastq" : "${prefix}.unclassified#.fastq"
     def classified_option = save_output_fastqs ? "--classified-out ${classified}" : ""
     def unclassified_option = save_output_fastqs ? "--unclassified-out ${unclassified}" : ""
-    def readclassification_option = save_reads_assignment ? "--output ${prefix}.kraken2.classifiedreads.txt" : ""
+    def readclassification_option = save_reads_assignment ? "--output ${prefix}.kraken2.classifiedreads.txt" : "--output /dev/null"
     def compress_reads_command = save_output_fastqs ? "pigz -p $task.cpus *.fastq" : ""
 
     """