replication mode: fix wrong available store list (#7222)

[ti-chi-bot]

This is an automated cherry-pick of #7222

What problem does this PR solve?

Issue Number:

What is changed and how does it work?

As now canSync and hasMajority are calculated using placement rules, we can contain stores that have only learners in avalable stores list.

This PR also fix a minor bug that relates to available stores id comparsion.

Check List

Tests

• Unit test

Related changes

• Need to cherry-pick to the release branch

Release note

None.

[ti-chi-bot]

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[ti-chi-bot]

@ti-chi-bot: The following test failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
idc-jenkins-ci/build	9f67bab	link	true	/test build

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