Escape spaces found while parsing GPO XMLNS tags

[willchenmark]

What does this PR do?

What issues does this PR fix or reference?

Escapes spaces found in XMLNS urls in Windows GPO documents with %20
Closes #66992

Previous Behavior

Spaces would not be escaped, breaking lgpo state application.

New Behavior

Spaces are properly escaped allow lgpo state application to operate correctly.

Merge requirements satisfied?

[NOTICE] Bug fixes or features added to Salt require tests.

• Docs
• Changelog - https://docs.saltproject.io/en/master/topics/development/changelog.html
• Tests written/updated

Commits signed with GPG?

No

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PR Guidelines.

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[twangboy]

Let me know if you need help writing tests for this. Looks like a simple unit test on the _encode_xmlns_url function would be enough. And a changelog as well.

[twangboy]

Also, let's make this fix on the 3006.x branch.

[twangboy]

OK, I added a test and created a change log. I also rebased on the 3006.x branch.