chore(deps): update dependency microsoft.data.sqlclient to 6.1.1 (#3193)

This PR contains the following updates:

| Package | Change | Age | Confidence |
|---|---|---|---|
| [Microsoft.Data.SqlClient](https://aka.ms/sqlclientproject)
([source](https://redirect.github.com/dotnet/sqlclient)) | `6.1.0` ->
`6.1.1` |
[![age](https://developer.mend.io/api/mc/badges/age/nuget/Microsoft.Data.SqlClient/6.1.1?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![confidence](https://developer.mend.io/api/mc/badges/confidence/nuget/Microsoft.Data.SqlClient/6.1.0/6.1.1?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|

---

### Release Notes

<details>
<summary>dotnet/sqlclient (Microsoft.Data.SqlClient)</summary>

###
[`v6.1.1`](https://redirect.github.com/dotnet/sqlclient/blob/HEAD/CHANGELOG.md#Stable-Release-611---2025-08-14)

This update includes the following changes since the [6.1.0](6.1.0.md)
release:

##### Fixed

- Reverted changes related to improving partial packet detection, fixup,
and replay functionality. This revert addresses regressions introduced
in 6.1.0.
([#&#8203;3556](https://redirect.github.com/dotnet/SqlClient/pull/3556))
- Applied reference assembly corrections supporting vector, fixed JSON
tests, and ensured related tests are enabled.
[#&#8203;3562](https://redirect.github.com/dotnet/SqlClient/pull/3562)
- Fixed `SqlVector<T>.Null` API signature in Reference assembly.
[#&#8203;3521](https://redirect.github.com/dotnet/SqlClient/pull/3521)

##### Changed

- Upgraded `Azure.Identity` and other dependencies to newer versions.
([#&#8203;3538](https://redirect.github.com/dotnet/SqlClient/pull/3538))
([#&#8203;3552](https://redirect.github.com/dotnet/SqlClient/pull/3552))

</details>

---

### Configuration

📅 **Schedule**: Branch creation - "before 8am" in timezone
Europe/London, Automerge - At any time (no schedule defined).

🚦 **Automerge**: Disabled by config. Please merge this manually once you
are satisfied.

♻ **Rebasing**: Whenever PR becomes conflicted, or you tick the
rebase/retry checkbox.

🔕 **Ignore**: Close this PR and you won't be reminded about this update
again.

---

- [ ] <!-- rebase-check -->If you want to rebase/retry this PR, check
this box

---

This PR was generated by [Mend Renovate](https://mend.io/renovate/).
View the [repository job
log](https://developer.mend.io/github/GoogleCloudPlatform/dotnet-docs-samples).

<!--renovate-debug:eyJjcmVhdGVkSW5WZXIiOiI0MS43MS4xIiwidXBkYXRlZEluVmVyIjoiNDEuNzEuMSIsInRhcmdldEJyYW5jaCI6Im1haW4iLCJsYWJlbHMiOltdfQ==-->

Author: renovate-bot

cloud-sql/sql-server/CloudSql.csproj

@@ -6,7 +6,7 @@
 
   <ItemGroup>
     <PackageReference Include="Google.Cloud.Diagnostics.AspNetCore3" Version="5.3.0" />
-    <PackageReference Include="Microsoft.Data.SqlClient" Version="6.1.0" />
+    <PackageReference Include="Microsoft.Data.SqlClient" Version="6.1.1" />
     <PackageReference Include="Polly" Version="8.6.3" />
   </ItemGroup>