Update Dockerfile

Signed-off-by: techopsmasters <163403479+techopsmasters@users.noreply.github.com>

react-express-mysql/backend/Dockerfile

@@ -33,15 +33,12 @@ COPY . /code
 CMD [ "node", "src/index.js" ]
 
 FROM development as dev-envs
-RUN <<EOF
-apt-get update
-apt-get install -y --no-install-recommends git
-EOF
-
-RUN <<EOF
-useradd -s /bin/bash -m vscode
-groupadd docker
+RUN apt update && \
+apt install -y --no-install-recommends git
+
+RUN useradd -s /bin/bash -m vscode && \
+groupadd docker && \
 usermod -aG docker vscode
-EOF
+
 # install Docker tools (cli, buildx, compose)
 COPY --from=gloursdocker/docker / /