Updating the docstring of `TwirlingOptions` for more clarity

[SamFerracin]

Summary

Adds more details on the values of num_randomizations and shots_per_randomization when one or both are set to "auto".

Details and comments

Fixes #1726

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:white_check_mark: SamFerracin
:x: Samuele Ferracin

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[coveralls]

Pull Request Test Coverage Report for Build 9568054526

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 82.304%

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Totals
Change from base Build 9568032754:	0.0%
Covered Lines:	6037
Relevant Lines:	7335

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💛 - Coveralls

[coveralls]

Pull Request Test Coverage Report for Build 9569665961

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 82.304%

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Totals
Change from base Build 9568032754:	0.0%
Covered Lines:	6037
Relevant Lines:	7335

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💛 - Coveralls

[coveralls]

Pull Request Test Coverage Report for Build 9571282610

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 82.0%

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Totals
Change from base Build 9569323918:	0.0%
Covered Lines:	6077
Relevant Lines:	7411

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💛 - Coveralls

[github-actions[bot]]

Pull Request Test Coverage Report for Build 9571543030

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 82.0%

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Totals
Change from base Build 9569323918:	0.0%
Covered Lines:	6077
Relevant Lines:	7411

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💛 - Coveralls

[coveralls]

Pull Request Test Coverage Report for Build 9571543030

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 82.0%

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Totals
Change from base Build 9569323918:	0.0%
Covered Lines:	6077
Relevant Lines:	7411

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💛 - Coveralls