Fix bsc#1209302: add some hints about KIWI extensions and dependencies for SLES

[tomschr]

SUSE Linux Enterprise Server (SLES) has KIWI as a package. However, some KIWI extensions and their dependencies can be unavailable.

This commit introduces a new section which deals with this aspect.

Fixes bsc#1209302.

Changes proposed in this pull request:

• Add new section about "Installation for SUSE Linux Enterprise Server"
• Describe the general issue when using KIWI extensions on SLES.
  Keep in mind, this was deliberately kept general to fit all extensions.

[mairda]

I believe that "However, if your rely on some extensions for..." is not valid English. due to the way "your" is used in-place. I assume a more equitable version is of a form similar to: "However, if your attempted installation shows reliance on some extensions for...". I'm sorry I can't find a way to say it as a reviewer.

[tomschr]

I believe that "However, if your rely on some extensions for..." is not valid English. due to the way "your" is used in-place.

Yes, thanks @mairda. That was a typo. Should be "you" instead of "your":

However, if you rely on some extensions for {kiwi}, either the extension
itself or any dependencies might not be available for your service pack.

I see your point. We could maybe extend the above paragraph and weave into "installation". Taking the "extension" -> "plugin" into account, I get this:

However, during installation, some plugins for {kiwi} may be required.
If your workflow relies on such plugins, either the plugin itself
or any dependencies might not be available for your service pack.

Better?

[schaefi]

Thanks for your effort on the docs. This makes complete sense to me and I think we could make it more clear by pointing out an example. See my review comments. Thanks much

[schaefi]

looks good to me

[tomschr]

If anything else needs to be corrected, let me know.

[mairda]

If anything else needs to be corrected, let me know.

Ultra pedantic and not things I demand, but...

• I believe docs.python.org and the community calls them "modules" rather than "extensions" or "plugins"
• pip is python version specific, there are probably multiple versions of python and pip on a given host mostly from the python 3.8 through python 3.11 version range. On Tumbleweed /bin/pip is a link to alts that selects the highest installed version to run. It may require more care for a specific purpose, e.g. pip-<version> if KIWI is configured to operate on another version of python than the latest installed.