Feat(queryToObject): add option to handle arrays

What does this MR do?

This MR adds an option to handle arrays in queryToObject. It is related to this MR where we added the option to spread values into an array when using mergeUrlParams. This handles the opposite case, where we need to read from the window.locaiton.search and turn it into a query object.

This is a stepping stone to implement the filter controls for the Merge Request Page.

Screenshots

This is not being used, yet, and therefore has no visual change.

Does this MR meet the acceptance criteria?

Conformity

• [-] Changelog entry
• [-] Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• [-] Database guides
• Separation of EE specific content

Availability and Testing

No real risk involved with this change. It adds a new option, which is not being used, yet. It also adds tests to ensure that the behavior works as expected.

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers
• [-] Informed Infrastructure department of a default or new setting change, if applicable per definition of done

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
• [-] The MR includes necessary changes to maintain consistency between UI, API, email, or other methods
• [-] Security reports checked/validated by a reviewer from the AppSec team

Related to #229266 (closed) and !39629 (merged)