Update Dockerfile

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

nginx-aspnet-mysql/backend/Dockerfile

@@ -15,16 +15,12 @@ CMD ["dotnet", "build", "-c", "-o", "/build"]
 
 FROM builder as dev-envs
 
-RUN <<EOF
-apt-get update
-apt-get install -y git
-EOF
-
-RUN <<EOF
-useradd -s /bin/bash -m vscode
-groupadd docker
+RUN apt update && \
+apt-get install - 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 / /