Description of problem:
The example of `oc adm catalog build` wrong:
Examples:
  # Build an operator catalog from an appregistry repo and store in a file
  oc adm catalog mirror --appregistry-org=redhat-operators --to=file://offline/redhat-operators:4.3

Version-Release number of selected component (if applicable):
[jzhang@dhcp-140-36 ~]$ oc version
Client Version: 4.4.0-0.nightly-2020-02-04-032141

How reproducible:
always

Steps to Reproduce:
1. Check the `oc adm catalog build` help info.

Actual results:
It displays the `oc adm catalog mirror`. 
[jzhang@dhcp-140-36 ~]$ oc adm catalog build --help
Builds a catalog container image from a collection operator manifests.

 Extracts the contents of a collection of operator manifests to disk, and builds them into an operator registry catalog
image.

Usage:
  oc adm catalog build [flags]

Examples:
  # Build an operator catalog from an appregistry repo and store in a file
  oc adm catalog mirror --appregistry-org=redhat-operators --to=file://offline/redhat-operators:4.3
  
  # Build an operator catalog from an appregistry repo and mirror to a registry
  oc adm catalog mirror --appregistry-org=redhat-operators --to=quay.io/my/redhat-operators:4.3


Expected results:
The output `oc adm catalog mirror` should be `oc adm catalog build`.

Additional info: