Add optional isChevronOnlyClickTrigger and labelComponent props to forst-expand

[anhuynh]

Overview

Summary

Adds two optional props to frost-expand:

• isChevronOnlyClickTrigger is a flag that allows the consumer to specify that the chevron should be the only clickable area to expand/close.
• labelComponent allows the consumer to use a custom component for the label instead of a plain string value.

Issue Number(s)

• Closes #555

Screenshots or recordings

isChevronOnlyClickTrigger set to true:

A custom component passed in as labelComponent:

Checklist

• [x] I have added tests that prove my fix is effective or that my feature works
• [x] I have evaluated if the README.md documentation needs to be updated
• [x] I have evaluated if the /tests/dummy/ app needs to be modified
• [ ] I have evaluated if DocBlock headers needed to be added or updated
• [x] I have verified that lint and tests pass locally with my changes
• [ ] If a fork of a dependent package had to be made to address the issue this PR closes:
  • [ ] I noted in the fork's README.md the reason the fork was created
  • [ ] I have opened an upstream issue detailing what was deficient about the dependency
  • [ ] I have opened an upstream PR addressing this deficiency
  • [ ] I have opened an issue in this repository to track this PR and schedule the removal of the usage of the fork

Semver

This project uses semver, please check the scope of this PR:

• [ ] #none#
• [ ] #patch#
• [x] #minor#
• [ ] #major#

CHANGELOG

• Added isChevronOnlyClickTrigger and labelComponent props to frost-expand