Bump MongoDB.Driver from 2.15.0 to 2.15.1

Bumps [MongoDB.Driver](https://github.com/mongodb/mongo-csharp-driver) from 2.15.0 to 2.15.1.
- [Release notes](https://github.com/mongodb/mongo-csharp-driver/releases)
- [Commits](mongodb/mongo-csharp-driver@v2.15.0...v2.15.1)

---
updated-dependencies:
- dependency-name: MongoDB.Driver
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

src/MongoDB.Abstracts/MongoDB.Abstracts.csproj

@@ -8,7 +8,7 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="MongoDB.Driver" Version="2.15.0" />
+    <PackageReference Include="MongoDB.Driver" Version="2.15.1" />
   </ItemGroup>
 
 </Project>