Bump Google.Protobuf in /src/ApiGateways/Mobile.Bff.Shopping/aggregator

Bumps [Google.Protobuf](https://github.com/protocolbuffers/protobuf) from 3.14.0 to 3.15.0.
- [Release notes](https://github.com/protocolbuffers/protobuf/releases)
- [Changelog](https://github.com/protocolbuffers/protobuf/blob/master/generate_changelog.py)
- [Commits](https://github.com/protocolbuffers/protobuf/compare/v3.14.0...v3.15.0)

---
updated-dependencies:
- dependency-name: Google.Protobuf
  dependency-type: direct:production
...

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

src/ApiGateways/Mobile.Bff.Shopping/aggregator/Mobile.Shopping.HttpAggregator.csproj

@@ -16,7 +16,7 @@
   <ItemGroup>
     <PackageReference Include="AspNetCore.HealthChecks.UI.Client" Version="5.0.1" />
     <PackageReference Include="AspNetCore.HealthChecks.Uris" Version="5.0.1" />
-    <PackageReference Include="Google.Protobuf" Version="3.14.0" />
+    <PackageReference Include="Google.Protobuf" Version="3.15.0" />
     <PackageReference Include="Grpc.AspNetCore.Server.ClientFactory" Version="2.34.0" />
     <PackageReference Include="Grpc.Core" Version="2.34.0" />
     <PackageReference Include="Grpc.Net.ClientFactory" Version="2.34.0" />