Fix mismatching type of ConsistencyPolicy with docstring

[allenkim0129]

Description

The typehint for ConsistencyPolicy in docstring and actual code were mismatching. This fix will sync the typehints for them.

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• The pull request does not introduce [breaking changes]
• CHANGELOG is updated for new features, bug fixes or other significant changes.
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[Copilot]

Pull Request Overview

This PR fixes a type annotation mismatch for the ConsistencyPolicy attribute in the DatabaseAccount class. The docstring type hint and actual code implementation had inconsistent type annotations.

• Updates docstring type annotation from Dict[str, Union[str, int]] to dict[str, str]
• Updates instance variable type annotation from Optional[UserConsistencyPolicy] to Optional[dict[str, str]]

[github-actions]

API Change Check

APIView identified API level changes in this PR and created the following API reviews

azure-cosmos

[annatisch]

Is this always going to be dict[str, str]? We don't want to change this later.

[allenkim0129]

Yes, the type will always be dict[str, str]

[annatisch]

Just to clarify, I was referring specifically to the value type - there's never going to be ints or booleans in this dictionary?
Unless something is a protocol that requires a mapping of strings, we usually stick with dict[str, Any].
But if your service mandates that these be string properties, then this is fine.

[tvaron3]

LGTM