[CI] Add pytest markers to current tests and update the doc. (#577)

Signed-off-by: Alicia <115451386+congw729@users.noreply.github.com>
Co-authored-by: Hongsheng Liu <liuhongsheng4@huawei.com>

tests/utils.py

@@ -495,18 +495,8 @@ def hardware_test(*, res: dict[str, str], num_cards: int | dict[str, int] = 1):
             raise ValueError(f"Unsupported platform: {platform}")
         all_marks.extend(marks)
 
-    create_new_process_flag = False
-    for cards in num_cards_dict.values():
-        if cards > 1:
-            create_new_process_flag = True
-            break
-
     def wrapper(f: Callable[_P, None]) -> Callable[_P, None]:
-        if create_new_process_flag:
-            # only for distributed tests
-            func = create_new_process_for_each_test()(f)
-        else:
-            func = f
+        func = f
         for mark in reversed(all_marks):
             func = mark(func)
         return func