Bump Microsoft.Identity.Web.MicrosoftGraphBeta from 1.8.0 to 1.8.1

Bumps [Microsoft.Identity.Web.MicrosoftGraphBeta](https://github.com/AzureAD/microsoft-identity-web) from 1.8.0 to 1.8.1.
- [Release notes](https://github.com/AzureAD/microsoft-identity-web/releases)
- [Changelog](https://github.com/AzureAD/microsoft-identity-web/blob/master/changelog.md)
- [Commits](AzureAD/microsoft-identity-web@1.8.0...1.8.1)

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

src/GraphWebhooks-Core/GraphWebhooks-Core.csproj

@@ -33,7 +33,7 @@
     <PackageReference Include="Microsoft.AspNetCore.Hosting" Version="2.2.7" />
     <PackageReference Include="Microsoft.AspNetCore.SignalR.Common" Version="5.0.4" />
     <PackageReference Include="Microsoft.AspNetCore.SignalR.Core" Version="1.1.0" />
-    <PackageReference Include="Microsoft.Identity.Web.MicrosoftGraphBeta" Version="1.8.0" />
+    <PackageReference Include="Microsoft.Identity.Web.MicrosoftGraphBeta" Version="1.8.1" />
     <PackageReference Include="Microsoft.Identity.Web.UI" Version="1.8.1" />
     <PackageReference Include="Microsoft.VisualStudio.Web.BrowserLink" Version="2.2.0" />
     <PackageReference Include="Microsoft.AspNetCore.Authorization" Version="5.0.4" />