[EuiStat] Allow customizing the render of the title and description HTML tags

[ashikmeerankutty]

Summary

Fixes #3676

Added two new props titleElement and descriptionElement to be used for customizing title and render HTML tags

Checklist

• Check against all themes for compatibility in both light and dark modes
• Checked in mobile
• Checked in IE11 and Firefox
• Props have proper autodocs
• Added documentation
  - [ ] Checked Code Sandbox works for the any docs examples
• Added or updated jest tests
• Checked for breaking changes and labeled appropriately
• Checked for accessibility including keyboard-only and screenreader modes
• A changelog entry exists and is marked appropriately

[kibanamachine]

Since this is a community submitted pull request, a Jenkins build has not been kicked off automatically. Can an Elastic organization member please verify the contents of this patch and then kick off a build manually?

[ashikmeerankutty]

There is an issue with screenreader now :

• If an element other than a string is provided. the screenreader p is shown as [object Object] due to
  

  eui/src/components/stat/stat.tsx

  Lines 139 to 141 in c19ca9f

  	<Fragment>
  	{reverse ? `${title} ${description}` : `${description} ${title}`}
  	</Fragment>

[chandlerprall]

The screen reader issue can be resolved by removing them from the string interpolation:

      <p>
        {isLoading ? (
          <EuiI18n token="euiStat.loadingText" default="Statistic is loading" />
        ) : (
          reverse ? <>{title} {description}</> : <>{description} {title}</>
        )}
      </p>

[ashikmeerankutty]

The screen reader issue can be resolved by removing them from the string interpolation:

      <p>
        {isLoading ? (
          <EuiI18n token="euiStat.loadingText" default="Statistic is loading" />
        ) : (
          reverse ? <>{title} {description}</> : <>{description} {title}</>
        )}
      </p>

Thanks, but here still elements are wrapped in p. so the warning can be found again

[chandlerprall]

One small request, otherwise this looks good to me

[ashikmeerankutty]

@chandlerprall Thanks for the review. Changes committed 👍

[chandlerprall]

Thanks @ashikmeerankutty! I'll approve&merge on passing CI

jenkins test this

[kibanamachine]

Preview documentation changes for this PR: https://eui.elastic.co/pr_3693/

[chandlerprall]

Changes LGTM, tested locally