fix: handle potential null values in workout description checks

Author: costa-alex

boot/src/main/kotlin/org/freekode/tp2intervals/app/workout/WorkoutService.kt

@@ -436,8 +436,8 @@ class WorkoutService(
 
         return externalData.trainingPeaksId != null &&
             externalData.trainerRoadId != null &&
-            workout.details.description.contains(
+            workout.details.description?.contains(
                 ExternalData.DESCRIPTION_SEPARATOR
-            )
+            ) == true
     }
 }

boot/src/main/kotlin/org/freekode/tp2intervals/infrastructure/platform/trainingpeaks/workout/TrainingPeaksWorkoutRepository.kt

@@ -196,9 +196,9 @@ class TrainingPeaksWorkoutRepository(
         }
 
         require(
-            workout.details.description.contains(
+            workout.details.description?.contains(
                 ExternalData.DESCRIPTION_SEPARATOR
-            )
+            ) == true
         ) {
             "Refusing to delete a workout not managed by the application"
         }
@@ -226,9 +226,9 @@ class TrainingPeaksWorkoutRepository(
 
         return externalData.trainingPeaksId != null &&
             externalData.trainerRoadId != null &&
-            workout.details.description.contains(
+            workout.details.description?.contains(
                 ExternalData.DESCRIPTION_SEPARATOR
-            )
+            ) == true
     }
 
 }