Reduce code complexity in GoogleChart

[nfmohit]

Feature Description

This is a follow-up of #4895, which introduces the complexity rule in ESLint. This resulted in the following lint error:

.../wordpress/wp-content/plugins/google-site-kit/assets/js/components/GoogleChart.js
  53:16  error  Function 'GoogleChart' has a complexity of 22. Maximum allowed is 20  complexity

This is the component in question.

While the error is currently ignored, the aim of this issue is to reduce said complexity.

---

Do not alter or remove anything below. The following sections will be managed by moderators only.

Acceptance criteria

• The ESLint ignore for complexity should be removed from the component identified in the title
• The component should be refactored to reduce the complexity to be within the acceptable range set by the current rule

Implementation Brief

• Using google-site-kit/assets/js/components/GoogleChart.js,
  • Remove ESLint ignore for complexity
  • Extract the logic to set modifiedData, loadingWidthToUse, loadingHeightToUse, combinedChartEvents, and chartOptions into individual functions
  • Use newly created functions to deliver props to <Chart />

Test Coverage

• No new tests are needed

QA Brief

• Check Google Charts appearance across this site - all functionality should remain the same

Changelog entry

• Reduce code complexity in GoogleChart component.

[aaemnnosttv]

@nfmohit it should come up later if this didn't happen, but it's probably a good idea to mention removing the related ESLint ignore rule here as well :) (I've updated it for completeness)

IB ✅

[wpdarren]

QA Update: ✅

Verified:

• Checked Google Charts appearance across this site to check that all functionality remains the same
  • Tested main and entity dashboard with live data (oi.ie)
  • Tested main and entity dashboard with gathering and zero data states
  • Tested main and entity view only dashboard
  • Tested the Site Kit widget on WP dashboard
  • Confirmed that there are no new warnings or errors in the console