docs(bulk-selection): Updates docs, images, and adds behavior guidance.

[edonehoo]

Closes #4871

Closes #4620

docs link: https://pf-org--pr-4938-site.surge.sh/patterns/bulk-selection

I refactored the page/images a bit because it was otherwise too hard to fit the new info in. But technically the info for the issue is in https://pf-org--pr-4938-site.surge.sh/patterns/bulk-selection#behavior

[patternfly-build]

Preview: https://pf-org--pr-4938-site.surge.sh

[lboehling]

Hey Erin! Thanks for writing this up and apologies for the delayed review! A couple of edits:

---

"Text label: Displays the number of selected items. When clicked, opens and closes the selection menu.”



the text label is associated with the checkbox in these examples, so clicking it will actually change the selection state not open the menu. Since the expected behavior is for the text label to open the menu, these examples should use the following split toggle variant, where the checkbox is separated with the divider instead of the caret: (note our demos and examples in the places notes in #4620 should use this split variant when a text label is shown in bulk select)

---

These examples are confusing to me — a row will always have a fully selected checkbox since the row itself cannot be partially selected. The “-“ would only apply in the bulk selector itself not on the individual rows.




---

This image conflicts with the following guidance that “Select none” should be disabled when nothing is selected. Should update the image to have select none disabled, since its unchecked.