fix(project): change config merge priority

[Alex Jank (jankal)]

Having the following configurations:

File: shopware-project.staging.yml

url: https://xyz.nuonic.dev
include:
    - .shopware-project.base.yml
sync:
    config:
        - settings:
              core.store.licenseHost: xyz.nuonic.dev

File: shopware-project.base.yml

admin_api:
    client_id: ${SHOPWARE_CLI_CLIENT_ID}
    client_secret: ${SHOPWARE_CLI_CLIENT_SECRET}
dump:
    where:
        customer: "email LIKE '%@nuonic.de' OR email LIKE '%@xyz.com'"
    nodata:
        - promotion
        - promotion_cart_rule
        - promotion_discount
        - promotion_discount_prices
        - promotion_discount_rule
        - promotion_individual_code
        - promotion_order_rule
        - promotion_persona_customer
        - promotion_persona_rule
        - promotion_sales_channel
        - promotion_setgroup
        - promotion_setgroup_rule
        - promotion_translation
        - newsletter_recipient
        - order
        - order_address
        - order_customer
        - order_delivery
        - order_delivery_position
        - order_line_item
        - order_line_item_download
        - order_tag
        - order_transaction
        - order_transaction_capture
        - order_transaction_capture_refund
        - order_transaction_capture_refund_position
    rewrite:
        product_review:
            email: "faker.Internet.Email()"
        log_entry:
            provider: ""

Running any shopware-cli project ... --project-config shopware-project.staging.yml

The current merging order removes sync.config[0] from the merged config as it was nil in my shopware-project.base.yml. Changing the config merging order fixes this behavior and gives the topmost config precedence.

Soner (@shyim) maybe there is a better fix for this (smth like mergo.WithOverwriteWithEmptyValue)

[Soner (shyim)]

Thank you!