CC65352, 65353, 65354, 65355, 65356: Fixing code highlight

Hello, @mrbullwinkle,
This proposed file change comes from https://github.com/MicrosoftDocs/azure-docs.zh-tw/pull/101.
Could you review this contribution and help to merge if agreed?
Many thanks in advance.

Author: v-maudel

articles/application-insights/app-insights-api-filtering-sampling.md

@@ -50,7 +50,7 @@ To filter telemetry, you write a telemetry processor and register it with the SD
 
     Notice that Telemetry Processors construct a chain of processing. When you instantiate a telemetry processor, you pass a link to the next processor in the chain. When a telemetry data point is passed to the Process method, it does its work and then calls the next Telemetry Processor in the chain.
 
-    ``` C#
+    ```csharp
 
     using Microsoft.ApplicationInsights.Channel;
     using Microsoft.ApplicationInsights.Extensibility;
@@ -97,7 +97,7 @@ To filter telemetry, you write a telemetry processor and register it with the SD
     ```
 1. Insert this in ApplicationInsights.config:
 
-```XML
+```xml
 
     <TelemetryProcessors>
       <Add Type="WebApplication9.SuccessfulDependencyFilter, WebApplication9">
@@ -137,7 +137,7 @@ TelemetryClients created after this point will use your processors.
 #### Synthetic requests
 Filter out bots and web tests. Although Metrics Explorer gives you the option to filter out synthetic sources, this option reduces traffic by filtering them at the SDK.
 
-``` C#
+```csharp
 
     public void Process(ITelemetry item)
     {
@@ -178,7 +178,7 @@ If you only want to diagnose calls that are slow, filter out the fast ones.
 >
 >
 
-``` C#
+```csharp
 
 public void Process(ITelemetry item)
 {
@@ -251,13 +251,15 @@ If you provide a telemetry initializer, it is called whenever any of the Track*(
 
 In ApplicationInsights.config:
 
+```xml
     <ApplicationInsights>
       <TelemetryInitializers>
         <!-- Fully qualified type name, assembly name: -->
         <Add Type="MvcWebRole.Telemetry.MyTelemetryInitializer, MvcWebRole"/>
         ...
       </TelemetryInitializers>
     </ApplicationInsights>
+```
 
 *Alternatively,* you can instantiate the initializer in code, for example in Global.aspx.cs: