Added some nullable regions to get rid of compiler warnings and follow best practices

ScrumTaskboard/Controllers/UsersController.cs

@@ -18,6 +18,7 @@ namespace ScrumTaskboard.Controllers
         }
 
         // GET: api/sprint
+        #nullable enable
         [HttpGet]
         public async Task<ActionResult<IEnumerable<ScrumUser>>> GetUser([FromQuery]string? name)
         {
@@ -29,6 +30,7 @@ namespace ScrumTaskboard.Controllers
 
             return await filtered.ToListAsync();
         }
+        #nullable disable
 
         // GET: api/sprint/5
         [HttpGet("{id}")]