Adjust ORAN-O2 related doc per the kubernetes 1.24 behavior change

[Litao Gao]

Brief Description
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Page: https://docs.starlingx.io/admintasks/kubernetes/oran-o2-application-b50a0c899e66.html

We've found that the secret creation behavior has been changed in kubernetes 1.24 which is default version of current StarlingX code:

 "When a ServiceAccount is created, no more Secret is created automatically."

Severity
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Minor

Steps to Reproduce
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Expected Behavior
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Exra step is required for the secret creation for the ServiceAccount.

Actual Behavior
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This step is missing, since secrect was created automatically in previous version.

Reproducibility
---------------

100% reproducible

System Configuration
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Branch/Pull Time/Commit
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Last Pass
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Timestamp/Logs
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Test Activity
-------------

Workaround
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[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.opendev.org/c/starlingx/docs/+/864829

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/c/starlingx/docs/+/864829
Committed: https://opendev.org/starlingx/docs/commit/22f58200f6e675063bc596177c0d6e844c3307c9
Submitter: "Zuul (22348)"
Branch: master

commit 22f58200f6e675063bc596177c0d6e844c3307c9
Author: Litao Gao <email address hidden>
Date: Thu Nov 24 06:47:11 2022 -0500

    Adjustment for the kubernetes 1.24 behavior change

    In K8s 1.24, when a ServiceAccount is created, no
    more Secret is created automatically. Need to add
    extra steps for secret creation.

    Closes-bug: 1997750

    Signed-off-by: Litao Gao <email address hidden>
    Change-Id: Iffa965717b35c55e129e21eca79bfbb1f6668f5d