Bump dependency Google.Api.Gax to 4.12.1 (#3238)

Signed-off-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>
Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

Directory.Packages.props

@@ -95,7 +95,7 @@
     <PackageVersion Include="BenchmarkDotNet" Version="0.15.4" />
     <PackageVersion Include="CommandLineParser" Version="2.9.1" />
     <PackageVersion Include="GitHubActionsTestLogger" Version="2.4.1" />
-    <PackageVersion Include="Google.Api.Gax" Version="4.11.1" />
+    <PackageVersion Include="Google.Api.Gax" Version="4.12.1" />
     <PackageVersion Include="Google.Protobuf" Version="3.32.1" />
     <PackageVersion Include="Grpc" Version="2.46.6" />
     <PackageVersion Include="Grpc.AspNetCore.Server" Version="2.71.0" />