Use latest ProtoBufJsonConverter to support WellKnownTypes

[StefH]

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 92.08633% with 11 lines in your changes missing coverage. Please review.

Project coverage is 49.41%. Comparing base (eb7e6c3) to head (b626de7). Report is 6 commits behind head on master.

Files with missing lines	Patch %	Lines
src/WireMock.Net/Extensions/AnyOfExtensions.cs	33.33%	6 Missing :warning:
test/WireMock.Net.Tests/WireMockServer.Proxy.cs	0.00%	0 Missing and 2 partials :warning:
src/WireMock.Net/Matchers/ProtoBufMatcher.cs	88.88%	1 Missing :warning:
src/WireMock.Net/Util/ProtoBufUtils.cs	88.88%	1 Missing :warning:
...ireMock.Net.Tests/Grpc/WireMockServerTests.Grpc.cs	98.79%	1 Missing :warning:

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1161      +/-   ##
==========================================
+ Coverage   49.18%   49.41%   +0.22%     
==========================================
  Files         200      201       +1     
  Lines       35310    35419     +109     
==========================================
+ Hits        17368    17501     +133     
+ Misses      17475    17451      -24     
  Partials      467      467              

:umbrella: View full report in Codecov by Sentry.
:loudspeaker: Have feedback on the report? Share it here.

[StefH]

https://github.com/WireMock-Net/WireMock.Net/issues/1144