Use oc create secret instead of deprecated oc secrets subcommands

[soltysh]

openshift/origin#18093 deprecated several oc secrets sub commands. This PR changes our docs not to use them, but instead use the supported versions.

@openshift/team-documentation this will require also release notes, something along the lines:

OpenShfit 3.9 deprecates following oc secrets sub commands:   new, new-basicauth, new-dockercfg, new-sshauth in favor of oc create secret. 

[vikram-redhat]

Thanks @soltysh - I am assuming for 3.9 onwards, right?

[soltysh]

@vikram-redhat that's correct

[ahardin-rh]

These changes LGTM and I've noted this in our Release Note Tracker.
@stuartchuan Can you please QE these changes? Thanks!

[stuartchuan]

@ahardin-rh The changes LGTM, have verified.

[ahardin-rh]

@soltysh @stuartchuan Thank you!

[ahardin-rh]

[rev_history]
|xref:../dev_guide/builds/build_inputs.adoc#dev-guide-build-inputs[Builds -> Build Inputs]
|Removed deprecated oc secrets subcommands and replaced them with oc create secret commands.
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|xref:../dev_guide/managing_images.adoc#dev-guide-managing-images[Managing Images]
|Removed deprecated oc secrets subcommands and replaced them with oc create secret commands.
%
|xref:../dev_guide/service_accounts.adoc#dev-guide-service-accounts[Service Accounts]
|Removed deprecated oc secrets subcommands and replaced them with oc create secret commands.
%