Events: Swap out google maps on homepage for event list.

[StevenDufresne]

In order to use the event-list block on the front-page.html, we need to make the grouping optional.

This PR adds that functionality and swaps out the block on the homepage.

There is an incidental change where wp-block-wporg-google-map is removed from the block because:

1. We aren't using to style
2. The map block looks for that class and hides the block. Not sure why yet, probably don't need to investigate.

Users can control the grouping as follows:

<!-- wp:wporg/event-list {"groupByMonth":"true","limit":"500"} /-->