add endpoint activity GetById

Tsi1.Api/Tsi1.Api/Controllers/ActivityController.cs

@@ -36,6 +36,20 @@ namespace Tsi1.Api.Controllers
             return Ok(result.Data);
         }
 
+        [Authorize(Roles = UserTypes.FacultyAdmin + ", " + UserTypes.Professor + ", " + UserTypes.Student)]
+        [HttpGet("GetById/{activityId}")]
+        public async Task<IActionResult> GetById(int activityId)
+        {
+            var result = await _activityService.GetById(activityId);
+
+            if (result.HasError)
+            {
+                return BadRequest(result.Message);
+            }
+
+            return Ok(result.Data);
+        }
+
         [Authorize(Roles = UserTypes.FacultyAdmin + ", " + UserTypes.Professor)]
         [HttpPost("Create")]
         public async Task<IActionResult> Create(ActivityCreateDto newActivity)