[rc2] Cosmos: Use ExecutionStrategy for query execution

[Copilot]

Fixes #35692

Description
The Cosmos provider was not using ExecutionStrategy during query execution, which meant that transient failures during queries would not be retried according to the configured retry policy. The CosmosClientWrapper already received an IExecutionStrategy instance and used it for CRUD operations (Create, Replace, Delete, ReadItem), but it was not being used for query execution through ExecuteSqlQuery and ExecuteSqlQueryAsync.

Customer impact
Customers using the Cosmos provider may experience application failures during transient network issues or service unavailability when executing queries. Without ExecutionStrategy, these failures would not be automatically retried, leading to unnecessary exceptions that could have been handled transparently. There are no straightforward workarounds besides implementing custom retry logic at the application level.

How found
This was reported by a customer.

Regression
No. It's a missing part of a feature that has existed since the Cosmos provider's inception.

Testing
There's currently no way to verify this, we'll have to wait for customer feedback.

Risk
Low. The changes are minimal and surgical, only affecting the actual database call points in DocumentEnumerable and DocumentAsyncEnumerable while preserving all existing enumeration behavior. The ExecutionStrategy pattern is well-established in other providers.

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[AndriySvyryd]

@copilot Rewrite the PR summary using this template:

Fixes #{number}

**Description**
{Issue description}

**Customer impact**
{How does the reported issue affects customer's app? Are there workarounds?}

**How found**
{Was it customer reported or found during verification? How many customers are affected?}

**Regression**
{Is it a regression from a released version? Which one?}

**Testing**
{How the changes were tested}

**Risk**
{Low/Medium/High, argument why}

[Copilot]

@copilot Rewrite the PR summary using this template:

...

Updated the PR description using the requested template in commit bdbfbbd.

[artl93]

There's currently no way to verify this, we'll have to wait for customer feedback.

Not awesome, but understood.