feat: add context manager support for bentoml.client (#3402)

Address #3288

src/bentoml/client.py

@@ -20,6 +20,9 @@
 from .exceptions import BentoMLException
 from ._internal.service.inference_api import InferenceAPI
 
+if t.TYPE_CHECKING:
+    from types import TracebackType
+
 
 class Client(ABC):
     server_url: str
@@ -85,6 +88,28 @@ def wait_until_server_is_ready(host: str, port: int, timeout: int) -> None:
                 raise TimeoutError("The server took too long to get ready")
             time.sleep(1)
 
+    def __enter__(self):
+        return self
+
+    def __exit__(
+        self,
+        exc_type: type[BaseException] | None,
+        exc_value: BaseException | None,
+        traceback: TracebackType | None,
+    ) -> bool | None:
+        pass
+
+    async def __aenter__(self):
+        return self
+
+    async def __aexit__(
+        self,
+        exc_type: type[BaseException] | None,
+        exc_value: BaseException | None,
+        traceback: TracebackType | None,
+    ) -> bool | None:
+        pass
+
     @staticmethod
     def from_url(server_url: str) -> Client:
         server_url = server_url if "://" in server_url else "http://" + server_url