statistics: extend store label with store id

[HuSharp]

What problem does this PR solve?

Issue Number: Close #8337

before after

$ ./pd-ctl store label 1 zone=c
Success! The store's label is updated.

$ ./pd-ctl store label 2 zone=b
Success! The store's label is updated.

$ ./pd-ctl store label 3 zone=c
Success! The store's label is updated.

$ ./pd-ctl config set replication.location-labels "zone"
Success!

What is changed and how does it work?

Check List

Tests

• Unit test
• Manual test (add detailed scripts or steps below)

Release note

None.

[ti-chi-bot[bot]]

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[ti-chi-bot[bot]]

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