Added unit tests to "tox -e parallel" environment (#2123)

Author: Nusnus

tox.ini

@@ -153,15 +153,16 @@ commands =
     make clean
 
 [testenv:parallel]
-description = Run all integration tests in parallel
+description = Run all unit and integration tests in parallel
 allowlist_externals = tox
 setenv =
     PYTHONUNBUFFERED = 1
     PYTHONDONTWRITEBYTECODE = 1
 commands =
     tox -e \
+    3.12-unit,\
     3.12-linux-integration-py-amqp,\
     3.12-linux-integration-redis,\
     3.12-linux-integration-mongodb,\
     3.12-linux-integration-kafka \
-    -p -o -- --exitfirst -n auto --dist=loadscope {posargs}
+    -p -o -- --exitfirst {posargs}