Bump MongoDB.Driver from 2.4.0 to 2.19.0 in /SeleniumWebdriver

Bumps [MongoDB.Driver](https://github.com/mongodb/mongo-csharp-driver) from 2.4.0 to 2.19.0.
- [Release notes](https://github.com/mongodb/mongo-csharp-driver/releases)
- [Commits](mongodb/mongo-csharp-driver@v2.4.0...v2.19.0)

---
updated-dependencies:
- dependency-name: MongoDB.Driver
  dependency-type: direct:production
...

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

Author: dependabot[bot]

SeleniumWebdriver/packages.config

@@ -9,7 +9,7 @@
   <package id="log4net" version="2.0.10" targetFramework="net452" />
   <package id="Microsoft.AspNet.Razor" version="3.0.0" targetFramework="net452" />
   <package id="MongoDB.Bson" version="2.4.0" targetFramework="net452" />
-  <package id="MongoDB.Driver" version="2.4.0" targetFramework="net452" />
+  <package id="MongoDB.Driver" version="2.19.0" targetFramework="net452" />
   <package id="MongoDB.Driver.Core" version="2.4.0" targetFramework="net452" />
   <package id="Newtonsoft.Json" version="13.0.1" targetFramework="net452" />
   <package id="NLog" version="4.5.10" targetFramework="net452" />