ASP NET Core SQL Server Docker-Compose entry point bash script show errors on logs

Question

I'm dockerizing an app but the entry point script doesn't work. The app couldn't perform CRUD actions and shows the "failed logging in with sa" error. I checked out the database because I suspect that the database didn't get created and yes, it didn't. So I thought the problem has to be the entry point script:

#!/bin/sh
set -e

until dotnet database update; do
echo "SQL Server is starting up"
sleep 1
done

echo "SQL Server is up - executing command"
dotnet database update

This script doesn't stop the app from building but it shows this in the log:

./Setup.sh: 1: ./Setup.sh: #!/bin/bash
not found
./Setup.sh: 2: ./Setup.sh: 
not found
./Setup.sh: 3: set: Illegal option -

Here's the the docker file that's supposed to run the script above (named Migrations.Dockerfile):

FROM mcr.microsoft.com/dotnet/sdk:5.0 AS build

WORKDIR /src
COPY ["Project/Project.csproj", "Project/"]
COPY Setup.sh Project/Setup.sh

RUN dotnet tool install --global dotnet-ef

RUN dotnet restore "./Project/Project.csproj"
COPY . .
WORKDIR "/src/Project"

RUN /root/.dotnet/tools/dotnet-ef migrations add InitialMigrations

RUN chmod +x ./Setup.sh
CMD /bin/sh ./Setup.sh

And here's the docker-compose.yml file:

version: '3.4'

services:
  project:
    image: ${DOCKER_REGISTRY-}project
    build:
      context: .
      dockerfile: Project/Dockerfile
    ports:
      - "9080:80"
    depends_on: 
      - migrations
      - db
  db:
    image: mcr.microsoft.com/mssql/server:2019-latest
    environment:
        SA_PASSWORD: "W0WV3RYSTRONGPASSWORD!"
        ACCEPT_EULA: "Y"
    ports:
        - "14331:1433"
    depends_on: 
        - migrations
  migrations:
    build: 
        context: .
        dockerfile: Migrations.Dockerfile