Feature/dependabot 2021 08 23

[gregrickaby]

Closes #129
Closes #130
Closes #131
Closes #132
Closes #133

Description

This PR includes an update to @wordpress/scripts, which includes upgrading Webpack from 4 to 5! 🥳

This PR updates the following Node dependencies:

 @wordpress/scripts       ^17.1.0  →  ^18.0.0     
 @wordpress/block-editor   ^7.0.0  →   ^7.0.1     
 @wordpress/blocks        ^11.0.0  →  ^11.0.1     
 @wordpress/components    ^15.0.0  →  ^16.0.0     
 @wordpress/compose        ^5.0.0  →   ^5.0.1     
 @wordpress/data           ^6.0.0  →   ^6.0.1   

It also updates the following Composer dependencies:

 composer/composer (2.1.5 => 2.1.6)
 mck89/peast (v1.13.5 => v1.13.6)
 seld/phar-utils (1.1.1 => 1.1.2)

Screenshot

Front-end

Back-end

Steps to verify the solution

How will a stakeholder test this? Please list the steps:

1. gh pr checkout 134
2. npm i --legacy-peer-deps
3. npm run build
4. Verify block JS and styles appear on the front-end and in the block editor