az-logout: add page

[mfrw]

• The page (if new), does not already exist in the repo.
• The page is in the correct platform directory (common/, linux/, etc.)
• The page has 8 or fewer examples.
• The PR title conforms to the recommended templates.
• The page follows the content guidelines.
• The page description includes a link to documentation or a homepage (if applicable).

For: #6141

[einverne]

Looks good to me.

[CleanMachine1]

@mfrw remember to remove descriptions of authors unless they made a big difference to the page and delete the branch after merging