Python 3 Base image with mssql server client drivers

for use with django-pyodbc-azure

Usage:

DATABASES = {
    'default': {
        'ENGINE': 'sql_server.pyodbc',
        'HOST': 'RDS_HOSTNAME',
        'PORT': 'RDS_PORT',
        'NAME': 'RDS_DB_NAME',
        'USER': 'RDS_USERNAME',
        'PASSWORD': 'RDS_PASSWORD',
        'OPTIONS': {
            'driver': 'ODBC Driver 17 for SQL Server',
            'MARS_Connection': 'True',
        },
    }
}