[enterprise-4.14] OSDOCS-6143: Added vCenter requirements section to vSphere UPI docs

[openshift-cherrypick-robot]

This is an automated cherry-pick of #60436

/assign stevsmit

[openshift-ci-robot]

@openshift-cherrypick-robot: Could not make automatic cherrypick of [Jira Issue OSDOCS-6143](https://issues.redhat.com//browse/OSDOCS-6143) for this PR as the target version is not set for this branch in the jira plugin config. Running refresh:
/jira refresh

In response to this:

This is an automated cherry-pick of #60436

/assign stevsmit

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.

[openshift-ci-robot]

@openshift-ci-robot: This pull request references OSDOCS-6143 which is a valid jira issue.

In response to this:

@openshift-cherrypick-robot: Could not make automatic cherrypick of [Jira Issue OSDOCS-6143](https://issues.redhat.com//browse/OSDOCS-6143) for this PR as the target version is not set for this branch in the jira plugin config. Running refresh:
/jira refresh

In response to this:

This is an automated cherry-pick of #60436

/assign stevsmit

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.