fix pip install step

Author: ttngu207

.devcontainer/Dockerfile

@@ -3,7 +3,8 @@ FROM mcr.microsoft.com/devcontainers/python:3.7-bullseye
 
 RUN \
     apt update && \
-    apt-get install bash-completion graphviz default-mysql-client -y
+    apt-get install bash-completion graphviz default-mysql-client -y && \
+    pip install flake8 black faker ipykernel
 
 ENV DJ_HOST localhost
 ENV DJ_USER root

.devcontainer/devcontainer.json

@@ -15,7 +15,7 @@
 		"ghcr.io/eitsupi/devcontainer-features/jq-likes:1": {},
 		"ghcr.io/guiyomh/features/vim:0": {}
 	},
-	"onCreateCommand": "pip install flake8 black faker ipykernel datajoint",
+	"onCreateCommand": "pip install -r requirements.txt",
 	"postStartCommand": "MYSQL_VER=8.0 MINIO_VER=RELEASE.2022-08-11T04-37-28Z docker compose -f ./.devcontainer/local-docker-compose.yml down && MYSQL_VER=8.0 MINIO_VER=RELEASE.2022-08-11T04-37-28Z docker compose -f ./.devcontainer/local-docker-compose.yml up --build --wait",
 	"forwardPorts": [
 		80,