Fix depth issue

Author: LouisLeNezet

nextflow_schema.json

@@ -85,7 +85,8 @@
             "default": "",
             "properties": {
                 "depth": {
-                    "type": "integer",
+                    "type": "number",
+                    "minimum": 0,
                     "description": "Depth of coverage for the simulated data",
                     "default": 1,
                     "fa_icon": "fas fa-list-ol"