chore: deprecate no longer supported projectId and environment config settings (#240)

Author: daveleek

src/Unleash/UnleashSettings.cs

@@ -43,6 +43,7 @@ public class UnleashSettings
         /// <summary>
         /// Gets or sets an environment. Used for communication with backend api.
         /// </summary>
+        [Obsolete("No longer supported in recent versions of Unleash, scope API token accordingly instead. Will be removed in the next major version", false)]
         public string Environment { get; set; } = "default";
 
         /// <summary>
@@ -53,6 +54,7 @@ public class UnleashSettings
         /// <summary>
         /// Sets the project to fetch feature toggles for.
         /// </summary>
+        [Obsolete("No longer supported in recent versions of Unleash, scope API token accordingly instead. Will be removed in the next major version", false)]
         public string ProjectId { get; set; } = null;
 
         /// <summary>