Fix for detectron2 installation

Signed-off-by: Jael Gu <mengjia.gu@zilliz.com>

detectron.py

@@ -1,9 +1,6 @@
 from typing import List, Tuple
 import os
-try:
 import detectron2
-except ModuleNotFoundError:
-    os.system("pip install 'git+https://github.com/facebookresearch/detectron2.git'")
 from detectron2 import model_zoo
 from detectron2.config import get_cfg
 from detectron2.engine.defaults import DefaultPredictor

requirements.txt

@@ -1,4 +1,4 @@
 torch >= 1.8
 torchvision >= 0.9.0
-# detectron2
-# https://github.com/facebookresearch/detectron2/archive/refs/tags/v0.6.tar.gz
+detectron2@https://github.com/facebookresearch/detectron2/archive/refs/tags/v0.6.tar.gz
+# detectron2@git+https://github.com/facebookresearch/detectron2.git@v0.6#egg=detectron2