Add refresh rate options to dashboard header

What does this MR do?

Part of #204920 (closed)

Adds refresh rate options to dashboard header.

With this change, users will not only be able to refresh their dashboards manually, they be able to set the dashboard to refresh automatically by selecting a refresh rate.

Refresh rules:

• Data will be refresh every time the user selects a new option (except for Off)
• The refresh rate does not define how often the refreshes will occur. It defines the amount of time for reload after data is loaded.
  • The timer will not start until the data for all charts has been loaded.
• Data will not be fetched if the document is "hidden", such as in an inactive tab.

Screenshots

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

• 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

Closes #204920 (closed)