Embeds: Add Setting to Instagram Embeds to Hide Caption

### Impacted plugin

Jetpack

### What

Add an option to hide or include the caption on an Instagram post via the Instagram Embed Block.

### How

**Current:**
Currently, adding an Instagram Embed looks like this, and includes the entire post:

In some cases, an end user may wish to remove the caption. Adding the feature would bring the embed block in line with the now deprecated Instagram Shortcode which supported the `hidecaption=true` parameter.

**Instagram:**
Instagram's native embed option includes a checkbox to hide the caption:

**Ideal outcome:**
Here is an example of what the native feature shows when captions are enabled or disabled:

**Notes:**
This feature is useful to allow customers to natively use Jetpack's Embed feature instead of manually needing to copy the embed code from Instagram.

Start by locating the Instagram Embed Block in Jetpack and compare its current caption behavior with the deprecated Instagram Shortcode's hidecaption=true option and Instagram's native embed setting. Done means the block lets users hide or include the caption and produces the corresponding embed output.

Written by the indexing model from the issue text.