dependency update example no longer works with source integration and Git >= 26

[gilzow]

Where on docs.platform.sh should be changed?

https://docs.upsun.com/learn/tutorials/dependency-updates.html#2-automate-your-dependency-updates-with-a-cron-job
https://docs.platform.sh/learn/tutorials/dependency-updates.html#2-automate-your-dependency-updates-with-a-cron-job

What exactly should be updated?

AS of Git 26, when --fetch-branches is set to true (default) in a source integration, the git repository clone on platform.sh / upsun essentially becomes a read-only mirror. This prevents you from merging branches on the platform/upsun side.

Currently our example of updating your dependencies using a cron job + source operation at step #3 will no longer work in this scenario.

Additional context

I'm not 100% sure what we replace the example with. Will need to think about it for a bit.