Add shots to QuasiDistributions in primitives.Sampler

[ikkoham]

Summary

QuasiDistribution can have shots. This has been forgotten in previous implementations, but is important because the some algorithms use it.

This is the followup PR of #8137 (not released yet).

Part of #8754.

Details and comments

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[coveralls]

Pull Request Test Coverage Report for Build 3201920744

• 1 of 1 (100.0%) changed or added relevant line in 1 file are covered.
• 2 unchanged lines in 1 file lost coverage.
• Overall coverage remained the same at 84.739%

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Files with Coverage Reduction	New Missed Lines	%
qiskit/extensions/quantum_initializer/squ.py	2	79.78%

Totals
Change from base Build 3201920356:	0%
Covered Lines:	61840
Relevant Lines:	72977

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💛 - Coveralls