[fix] CodeFactor issues

Author: i4004

src/Etcd.Microsoft.Extensions.Configuration/EtcdApplicationEnvironment.cs

@@ -1,5 +1,4 @@
 using System;
-using System.IO;
 
 namespace Etcd.Microsoft.Extensions.Configuration;
 
@@ -15,7 +14,6 @@ public static class EtcdApplicationEnvironment
 
 	private static string? _connectionString;
 
-
 	/// <summary>
 	/// Gets or sets the connection string.
 	/// </summary>