Update parsing

Author: am11

src/BenchmarkDotNet/ConsoleArguments/ConfigParser.cs

@@ -776,8 +776,8 @@ internal static bool TryParse(string runtime, out RuntimeMoniker runtimeMoniker)
             int index = runtime.IndexOf('-');
 
             return index < 0
-                ? Enum.TryParse<RuntimeMoniker>(runtime.Replace(".", string.Empty), ignoreCase: true, out runtimeMoniker)
-                : Enum.TryParse<RuntimeMoniker>(runtime.Substring(0, index).Replace(".", string.Empty), ignoreCase: true, out runtimeMoniker);
+                ? Enum.TryParse<RuntimeMoniker>(runtime.Replace(".", string.Empty).Replace("_", string.Empty), ignoreCase: true, out runtimeMoniker)
+                : Enum.TryParse<RuntimeMoniker>(runtime.Substring(0, index).Replace(".", string.Empty).Replace("_", string.Empty), ignoreCase: true, out runtimeMoniker);
         }
     }
 }

src/BenchmarkDotNet/Environments/Runtimes/ClrRuntime.cs

@@ -66,7 +66,7 @@ internal static ClrRuntime GetCurrentVersion()
                 case "4.8":   return Net48;
                 case "4.8.1": return Net481;
                 default: // unlikely to happen but theoretically possible
-                    return new ClrRuntime(RuntimeMoniker.NotRecognized, $"net{version.Replace(".", null)}", $".NET Framework {version}");
+                    return new ClrRuntime(RuntimeMoniker.NotRecognized, $"net{version.Replace(".", null).Replace("_", null)}", $".NET Framework {version}");
             }
         }
     }