update k8s doc (#4008)
update k8s doc (#4008)

* update k8s doc

* Update k8s.md

add more detailed info

* Update k8s.md

Move section3.3 to section4
change title of section 4.1 to "How to retain executor logs for debugging"
add a note at the beginning of Section 3: "Please refer to section 4 for some know issues"
change wrong format of init_orca example
add consumption for "steps_per_epoch"

* Update k8s.md

update 4.5 how to set proper "steps_per_epoch" and "validation steps"

Co-authored-by: aqtjin <ebde4c3355432eb2090de47f143ee73401d9e3a6@outlook.com>
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