Add download parameters via mirror pull

[VaLosev]

1. Add the ability to download a specific release channel. Currently, the utility supports the "--deckhouse-tag" flag, which allows you to download only a specific DKP version (ignoring update channels).

Reason:
This is necessary to be able to download a specific DKP version without having to check which release is currently running on a specific update channel (alpha/beta/stable, etc.). Some clients use automated image downloads, but they have to manually match DKP versions with the corresponding channels.

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2. Enable incremental image downloads.

Reason:
Downloading ~350 images each time is time-consuming and expensive, especially on remote sites.

This feature will also be useful for information security departments. They won't have to re-validate a new delivery if they already approved a specific set of modules or packages when downloading the images for the first time.

Additional information:
We can add the ability to specify which DKP version an incremental bundle is required from. Then d8 will go to the official repository, look at the images included in that release, find the incremental bundle based on the images from the release it wants to download, and download only the missing images.