[Doc] Fix documentation mismatch for default argument

[TheRisenPhoenix]

Description

This fixes a mismatch in the documentation of the default value of the num_qvalue_nets argument in DiscreteSACLoss. The documentation said that default is 10, but in reality it is 2.

Motivation and Context

This is misleading.

Types of changes

What types of changes does your code introduce? Remove all that do not apply:

• Documentation (update in the documentation)

Checklist

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• I have read the CONTRIBUTION guide (required)
• My change requires a change to the documentation.
• I have updated the tests accordingly (required for a bug fix or a new feature).
• I have updated the documentation accordingly.

[pytorch-bot]

🔗 Helpful Links

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[vmoens]

Thanks :)