[CI] Adjust labeler rule for refactored architecture

Author: aobolensk

.github/labeler.yml

@@ -1,15 +1,17 @@
 'task:all':
-  - "tasks/all/**"
+  - "tasks/**/all"
 'task:mpi':
-  - "tasks/mpi/**"
+  - "tasks/**/mpi"
 'task:omp':
-  - "tasks/omp/**"
+  - "tasks/**/omp"
 'task:seq':
-  - "tasks/seq/**"
+  - "tasks/**/seq"
 'task:stl':
-  - "tasks/stl/**"
+  - "tasks/**/stl"
 'task:tbb':
-  - "tasks/tbb/**"
+  - "tasks/**/tbb"
+task:
+  - "tasks/**"
 ci:
   - ".github/**"
   - "appveyor.yml"