docs: add info about dependency management for vanilla ESM in browser

[earcam]

Please see #31944

[XhmikosR]

Thanks for the PR!

I notice two issues:

1. since the SRI hash changes on previews (because we build the latest code), we are getting SRI mismatch errors there. Unsure how to handle this, because hardcoding the values isn't an option :/

2. I'm also getting JS errors when I click the button with all browsers I tried:

   Uncaught TypeError: Popper.createPopper is not a function
       at Popover.show (tooltip.js:273:29)
       at Popover._enter (tooltip.js:598:15)
       at Popover.toggle (tooltip.js:191:17)
       at HTMLButtonElement.<anonymous> (tooltip.js:532:107)
       at HTMLButtonElement.i (event-handler.js:102:15)
   

[mdo]

I put together a test of this over at https://github.com/twbs/examples/tree/main/sass-js-esm. Loving the potential of this, and agreed our docs needs more guidance on the options available to developers for consuming our JS.

[mdo]

Replaced by #36414.