fix: latest build issues

[vijayraghav-io]

Fixes the following issues :

1. Avoid prefix DOCKER_BUILDKIT=0 in docker compose build command or docker compose up command.

• As per latest docker desktop versions and buildkit version , network: stack field is not required under build. This was required in legacy versions. Refer File - docker-compose.yaml
• Build-time Networking :The network: key within the build section (build: network: stack) is intended to specify the network mode for the RUN instructions during the image build process. BuildKit, Docker's modern build engine, does not support arbitrary custom networks (like stack) for this purpose. It primarily supports standard network modes such as host, none, or its default isolated bridge network.
  Reference: Docker's docker buildx build command documentation (which docker compose build now uses under the hood with BuildKit):
  https://docs.docker.com/reference/cli/docker/buildx/build/#network
  Reference - Missing git-init.sh and git-setup.sh and other problems #440

Before Fix	After Fix

2. Build process is trying to run database migrations (yarn db-deploy) during the image build phase. This won't work because the database service isn't available during build time.
   The following line - (File - Dockerfile)
   RUN yarn db-deploy
   RUN yarn --cwd packages/prisma seed-app-store
   are executed even before the database container is ready or started. Hence the issue after prisma migrations.
   Also as reported here - Missing git-init.sh and git-setup.sh and other problems #440
   The scripts/start.sh script already has these commands and executes after db is ready, hence removing these commands from docker file.

Before Fix	After Fix

3. The files git-init.sh and git-setup.sh are removed (from this PR ci: remove deprecated submodule code cal.com#20731)
   Hence the docker build is failing at a COPY cmd while trying to copy these files.

Before Fix	After Fix

[vijayraghav-io]

🙏