feat(GlTabs): add support for syncing active tab with query params

What does this MR do?

Related to #1377 (closed)

Adds a syncActiveTabWithQueryParams prop to GlTabs component. When this prop is set to true a query string will be synced with the active tab. The name of this query string is based off of the optional queryParamName prop that defaults to tab. The value of the query string will be the index of the tab or, if set, the value of the query-param-value attribute set on the tab.

Video

Screen_Recording_2021-05-19_at_11.31.21_AM

Testing locally

When running yarn storybook, the components are rendered inside an <iframe>, so the component can't change the browser's URL. Instead, you can navigate directly to the <iframe>'d URL.

Follow the steps in the below screenshot:

Does this MR meet the acceptance criteria?

Conformity

• Code review guidelines.
• GitLab UI's contributing guidlines.
• [-] If it changes a Pajamas-compliant component's look & feel, the MR has been reviewed by a UX designer.
• [-] If it changes GitLab UI's documentation guidelines, the MR has been reviewed by a Technical Writer.
• If the MR changes a component's API, integration MR(s) have been opened in the following projects to ensure that the @gitlab/ui package can be upgraded quickly after the changes are released:
  • GitLab: gitlab!61951 (merged)
    • Will need to update a few snapshot tests because of the new props but this should be easy
  • CustomersDot: https://gitlab.com/gitlab-org/customers-gitlab-com/-/merge_requests/3271
    • Snapshot test failing due to switching order of some HTML attributes on an a tag. This is probably due to a different version of Bootstrap Vue and should be an easy fix.
  • Status Page: GlTabs not used
• Added the ~"component:*" label(s) if applicable.

Security

If this MR contains changes to processing or storing of credentials or tokens, authorization and authentication methods and other items described in the security review guidelines:

• [-] Label as security and @ mention @gitlab-com/gl-security/appsec
• [-] Security reports checked/validated by a reviewer from the AppSec team

Accessibility

If this MR adds or modifies a component, take a few moments to review the following:

• All actions and functionality can be done with a keyboard.
• Links, buttons, and controls have a visible focus state.
• All content is presented in text or with a text equivalent. For example, alt text for SVG, or aria-label for icons that have meaning or perform actions.
• Changes in a component’s state are announced by a screen reader. For example, changing aria-expanded="false" to aria-expanded="true" when an accordion is expanded.
• Color combinations have sufficient contrast.