[core] feat(MultistepDialog): tooltips on navigation buttons

[ohcnivek]

Fixes #5519

Checklist

• Includes tests
• Update documentation

Changes proposed in this pull request:

• adding an extra prop, tooltipContent, to abstractButton.tsx props, which by association enables the prop to exist on DialogStepButtonProps
• renders tooltip on dialog step button if tooltipContent prop exists (user should define when it exists / doesnt, checkout the example. packages/docs-app/src/examples/core-examples/multistepDialogExample.tsx)
• also adjusted the example in docs to reflect changes

Reviewers should focus on:

• typescript quality / implementation logic — followed what @adidahiya suggested in Add tooltip to MultistepDialog final button #5519

Screenshot

Screen.Recording.2022-09-10.at.1.47.00.AM.mov

[palantirtech]

Thanks for your interest in palantir/blueprint, @ohcnivek! Before we can accept your pull request, you need to sign our contributor license agreement - just visit https://cla.palantir.com/ and follow the instructions. Once you sign, I'll automatically update this pull request.

[adidahiya]

There's another issue here -- Tooltips don't play nicely with disabled Buttons. This edge case will be common with the tooltipContent, as users will likely be showing something in the tooltip when the button is disabled. See the Button docs for more info. It's better to use an AnchorButton.

I'll push a commit here to make these fixes.

[adidahiya]

docs preview build looks good 👍🏽