Fix bug where workflow can hang if the email parameter is set.

This fix moves all queue channel operations out of the onComplete block and into the main workflow.

Author: robsyme

subworkflows/local/utils_nfcore_sarek_pipeline/main.nf

@@ -183,6 +183,8 @@ workflow PIPELINE_COMPLETION {
     main:
     summary_params = paramsSummaryMap(workflow, parameters_schema: "nextflow_schema.json")
 
+    def multiqc_report_list = multiqc_report.toList()
+
     //
     // Completion email and summary
     //
@@ -195,7 +197,7 @@ workflow PIPELINE_COMPLETION {
                 plaintext_email,
                 outdir,
                 monochrome_logs,
-                multiqc_report.toList()
+                multiqc_report_list.getVal()
             )
         }