v0.13.3

• Updating some dependencies to avoid vulnerable packages:
  • SlackNet now depends on System.Net.Security 4.3.1 and System.Text.RegularExpressions 4.3.1.
  • SlackNet.AspNetCore now depends on System.Text.Encodings.Web 4.5.1.
  • SlackNet.AzureFunctions now depends on Microsoft.Azure.Functions.Worker.Core 1.17.0.