[hotfix] typo in the javadoc of the functions in KeyedStateStore

[almogtavor]

What is the purpose of the change

Minor typo hotfix in Javadoc. The typo is that multiple functions have the description of The descriptor defining the properties of the stats instead of The descriptor defining the properties of the state.

[flinkbot]

CI report:

• bad6b25153273923bdacf53d44653f816784be8c Azure: FAILURE

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