parser: add sample rate for analyze option

[winoros]

What problem does this PR solve?

Add new option SAMPLERATE to support collect samples by sample rate for statistics

What is changed and how it works?

Add new grammar

Check List

Tests

• Unit test

[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• tangenta

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[ti-chi-bot]

@winoros: PR needs rebase.

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[tangenta]

What is the unit? Percentage?