Description of problem:
During ROSA classic creation, The user has chosen a version <= 4.12.z and used custom VPC settings and enabled shared VPC options , related settings. Once the cluster installation is initiated , wizard reported a failure that minimum required version is 4.13.

To avoid all these complications , suggestion is to hide the shared VPC options from Networking > VPC Settings step for all unsupported version. 

How reproducible:

 Always

Steps to reproduce:

1. Launch OCM UI staging
2. Open ROSA wizard and control plane type as "Classic".
3. Fill all required information in each step and reach to "Cluster settings > Details" step.
4. Set the version to 4.12.z or lower and fill other field.
5. Click "Next" button.
6. Fill all required information in each step and reach to "Networking" step.
7. Check "Install into an existing VPC" and click "Next"
8. Check "Install into AWS shared VPC" and fill all required info.
9. Click "Next" button and proceed to next steps.
10. In "Review and create" page , Click on "Create cluster" button.
11. See the behavior.

Actual results:
The error reported to the user that shared VPC only supported in 4.13.9. This is confusing as there was no indication in any of the step that the feature is not supported the selected version i.e. 4.12.z in this case.
Expected results:
For better usability and make more clear, hide the shared VPC feature in wizard when unsupported version selected.