Analyzer: Suggested SqlConnection Use Pattern

**Conditions to Trigger Analzyer**
Within a `[Function]`-decorated method, where a SqlConnection is instantiated..

```csharp
using System;
using System.IO;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Azure.WebJobs;
using Microsoft.Azure.WebJobs.Extensions.Http;
using Microsoft.AspNetCore.Http;
using Microsoft.Extensions.Logging;
using Newtonsoft.Json;
using System.Data.SqlClient;

namespace TestManageConnectionApp
{
public static class SQLHTTPTrigger
{
[FunctionName("SQLHTTPTrigger")]
public static async Task Run(
[HttpTrigger(AuthorizationLevel.Function, "get", "post", Route = null)] HttpRequest req,
ILogger log)
{
log.LogInformation("C# HTTP trigger function processed a request.");

string connetionString;
SqlConnection cnn;
connetionString = @"Data Source=WIN-50GP30FGO75;Initial Catalog=Demodb;User ID=sa;Password=demol23";
cnn = new SqlConnection(connetionString);
cnn.Open();

string responseMessage = "This HTTP triggered function executed successfully.";

cnn.Close();
return new OkObjectResult(responseMessage);
}
}
}
```

**Diagnostic Level**
Warning

**How to Fix Violations**
Wrap SqlConnection instantiation in `using` statement, ex. https://github.com/cheenamalhotra/azurefunctions-sqlclient-example/blob/master/HttpTriggerSqlClient.cs

**Provide Code Fix**
Yes

**When to Suppress Analyzer Rule**
This rule should not be suppressed.

Start with the trigger conditions and code example in the issue, then locate the repository's analyzer and code-fix entry points and their existing tests. Done means the analyzer warns for the described SqlConnection pattern inside a [Function]-decorated method and offers the requested using-statement fix.

Written by the indexing model from the issue text.