Container Registry vue router breadcrumb

What does this MR do?

This MR is part of a series of merge requests to bring new UX and routing methods to the Container Registry. This enables the Container Registry pages to behave like a SPA using vue-router.

This MR is part four that implements the dynamic breadcrumb.

The breadcrumb does:

• read the current static breadcrumb and replace it
• replace the last entry of the breadcrumb with one tied to vue-router
• if the user is inside a 'child' route display an appropriate breadcrumb
• the styling of the breadcrumb and the divider is 'read' from the static breadcrumb

This new UX is behind the vue_container_registry_explorer feature flag so it can easily be reverted. No modifications have been made to the existing Container Registry code as part of this.

In addition, this MR fixes an issue with the bulk delete path

Screenshots

Root

Child

Screencapture

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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

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

Part of #23315 (closed)