Update Pages docs for further clarity on URL formats

What does this MR do and why?

Addresses remaining issues with Pages docs described in #385242 (comment 1533591429).

Specifically:

• Removes the use of project-slug without further definition. This addresses @kassio's feedback in !129378 (merged) regarding the need for a glossary or definition. The only uses of project-slug or project-path are now defined in-place. Furthermore, this example is not even necessary (see comment in diff).
• Makes entries in the table of examples consistent by removing the duplicate final row and updating the column title to specify that these are examples.

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