Poll block: Allow developers to disable styling panels in block settings

We're using the CrowdSignal plugin on a headless WordPress site. It enables us to easily create a poll in WordPress and use the CrowdSignal backend to track results. Since our site is headless, we've built our own frontend for the poll that fits in with our site's design.

In WordPress, the **Block styling** and **Button styling** panels in the block settings sidebar are non-functional for us, but we couldn't identify a straightforward way to remove them. It would be nice to have a filter or hook available to disable these panels users don't get confused while working with the block in the editor.

I'm sure this is a low-priority change in the grand scheme of things, but for those of us working with headless sites, options like this are great to have.

Start by locating the Poll block's editor settings entry point and the Block styling and Button styling panels in the block settings sidebar. Determine how a filter or hook could disable those panels, then verify that headless users no longer see them while the panels remain available by default.

Written by the indexing model from the issue text.