Description of problem:
Note : The issue seen with both staging and production hence in my opinion I don't think depends on recent ROSA v2 changes.

In ROSA wizard, once user search and select a compute node type from the "Compute node instance type" dropdown, then the compute node instance node type list shown only the selected node type category not all the list of compute types available. This looks wrong.
See the screen recordings  : computenodetypeissues.mp4

How reproducible:

always

Steps to Reproduce:

1. Open OCM UI staging.
2. Launch Rosa wizard and select control plane as "Classic"
3. Reach to "Default Machine pool" step.
4. Click on "Compute node instance type" dropdown.
5. Click the "Search" field and input the compute instance type, for ex "t3a"
6. Select the instance "t3a.xlarge".
7. Click on  "Compute node instance type" dropdown.
8. See the list of compute types.

Actual results:

At step 8, only list of node types from the category that belongs to the searched type is shown.

Expected results:

All available supported compute node types should show without any issue.