Remove `enable_geo_node_form_js` feature flag

What does this MR do?

Closes #118841 (closed)

The Geo Node Form has been officially re-written in Vue via 5 MRs mentioned in the issue above ⬆

This MR removes the feature flag and the no longer needed legacy code. This will officially switch the Geo Node Form to Vue for all users.

Breakdown of all cleanup in this MR:

geo/nodes/new.html.haml

1. Delete File
	- Replaced by `form.html.haml`

geo/nodes/edit.html.haml

1. Delete File
	- Replaced by `form.html.haml`

geo/nodes/_form.html.haml

1. Delete file
	- Form is in Vue now
            - Replaced by `form.html.haml`

geo/nodes/form.html.haml

1. Create file
	- Combines `new.html.haml` and `edit.html.haml`

application_settings_helper.rb:

1. Remove `repository_storages_options_for_select`
	 - Usage replaced by `repository_storages_options_json`

geo_helper.rb

1. Remove `selective_sync_type_options_for_select`
	- Usage replaced by `selective_sync_types_json`

nodes_controller.rb

1. Remove `push_feature_flag`
	- Feature flag is removed
    2. Send `new` and `edit` routes to `form.html.haml`
            - Combines views             

pages/geo/create

1. Delete folder and `index.js`
	- Requests are done by API now and no longer need this route for redirection

pages/geo/update

1. Delete folder and `index.js`
	- Requests are done by API now and no longer need this route for redirection

pages/geo/shared

1. Delete folder and `init_form.js`
	- Form is now bootstrapped in Vue and this file is no longer needed

pages/geo/new

1. Remove conditional render
	- Feature flag is removed
	- Form is bootstrapped by Vue and not `init_form.js`/HAML

pages/geo/edit

1. Remove conditional render
	- Feature flag is removed
	- Form is bootstrapped by Vue and not `init_form.js`/HAML

admin_geo_nodes_spec.rb

    1. Update spec
	- Feature flag is removed
	- Field names changed

qa/ee/page/admin/geo/nodes/new.rb

    1. Update selectors
            - Selector location changed

geo_node_form_core.vue

    1. Add QA Selectors
            - Moved from HAML

geo_node_form.vue

    1. Add QA Selectors
            - Moved from HAML

GIF

(Existing Functionality) Create New Node:

(Existing Functionality) Edit Node:

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