chore(deps): update dependency npgsql to 9.0.4 (#3226)

This PR contains the following updates:

| Package | Change | Age | Confidence |
|---|---|---|---|
| [Npgsql](https://redirect.github.com/npgsql/npgsql) | `9.0.3` ->
`9.0.4` |
[![age](https://developer.mend.io/api/mc/badges/age/nuget/Npgsql/9.0.4?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![confidence](https://developer.mend.io/api/mc/badges/confidence/nuget/Npgsql/9.0.3/9.0.4?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|

---

### Release Notes

<details>
<summary>npgsql/npgsql (Npgsql)</summary>

###
[`v9.0.4`](https://redirect.github.com/npgsql/npgsql/releases/tag/v9.0.4)

v9.0.4 contains several minor bug fixes.

[Milestone
issues](https://redirect.github.com/npgsql/npgsql/milestone/127?closed=1)

**Full Changelog**:
<npgsql/npgsql@v9.0.3...v9.0.4>

</details>

---

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Author: renovate-bot

cloud-sql/postgres/CloudSql.csproj

@@ -6,7 +6,7 @@
 
   <ItemGroup>
     <PackageReference Include="Google.Cloud.Diagnostics.AspNetCore3" Version="5.3.0" />
-    <PackageReference Include="Npgsql" Version="9.0.3" />
+    <PackageReference Include="Npgsql" Version="9.0.4" />
     <PackageReference Include="Polly" Version="8.6.4" />
   </ItemGroup>