Geo Node Form Regression - Relative URLs broken

What does this MR do?

Closes #337177 (closed)

A bug was identified with more complex paths used in GitLab that the Nodes forms were redirecting to absolute paths which ended up with the user hitting a 404.

Ex. Domain: https://gitlab.example.com/gitlab/ removed the gitlab parameter when redirecting resulting in the new path being https://gitlab.example.com/admin/geo/nodes rather than https://gitlab.example.com/gitlab/admin/geo/nodes

This approach to fixing this was to revert to using the Rails Path variable for the geo_nodes page. This was how the redirects were handled before the forms was converted to Vue.

Screenshots or Screencasts (strongly suggested)

Bug	Fix
Bug	Fix

How to setup and validate locally (strongly suggested)

1. Set up Geo on your GDK
2. Fetch/Checkout this branch on your Primary Node (gdk-primary)
3. Update your Primary Node's (gdk-primary) gdk.yml by adding relative_url_root: "/gitlab"
4. Run gdk reconfigure

For Geo Nodes Edit Form

1. Navigate to http://127:0:0:1/gitlab/admin/geo/nodes
2. Click Edit
3. Click Save changes or Cancel
4. Ensure you are redirected back to http://127:0:0:1/gitlab/admin/geo/nodes and not 404

For Geo Nodes Settings Form

1. Navigate to http://127:0:0:1/gitlab/admin/geo/settings
2. Click Cancel
3. Ensure you are redirected back to http://127:0:0:1/gitlab/admin/geo/nodes and not 404

Does this MR meet the acceptance criteria?

Conformity

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• I have self-reviewed this MR per code review guidelines.
• This MR does not harm performance, or I have asked a reviewer to help assess the performance impact. (Merge request performance guidelines)
• I have followed the style guides.
• This change is backwards compatible across updates, or this does not apply.

Availability and Testing

• I have added/updated tests following the Testing Guide, or it's not needed. (Consider all test levels. See the Test Planning Process.)
• I have tested this MR in all supported browsers, or it's not needed.
• I have informed the Infrastructure department of a default or new setting change per definition of done, or it's not needed.

Security

Does this MR contain changes to processing or storing of credentials or tokens, authorization and authentication methods or other items described in the security review guidelines? If not, then delete this Security section.

• [-] 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 #337177 (closed)