Add blank penalty for various language bindings. (#1234)

scripts/dotnet/OnlineRecognizerConfig.cs

@@ -25,6 +25,7 @@ namespace SherpaOnnx
             CtcFstDecoderConfig = new OnlineCtcFstDecoderConfig();
             RuleFsts = "";
             RuleFars = "";
+            BlankPenalty = 0.0F;
         }
         public FeatureConfig FeatConfig;
         public OnlineModelConfig ModelConfig;
@@ -69,6 +70,7 @@ namespace SherpaOnnx
 
         [MarshalAs(UnmanagedType.LPStr)]
         public string RuleFars;
-    }
 
-}
+        public float BlankPenalty;
+    }
+}