grpc: Set provider priority

[wlynch]

The 2 grpc packages are currently conflicting with each other:

2024/10/10 15:08:44 ERRO failed to build package: unable to build guest: unable to generate image: installing apk packages: error getting package dependencies: solving "opentelemetry-cpp-dev" constraint: resolving "opentelemetry-cpp-dev-1.17.0-r0.apk" deps:
resolving "opentelemetry-cpp-1.17.0-r0.apk" deps:
solving "so:libgpr.so.43" constraint:   grpc-1.66-1.66.2-r0.apk disqualified because grpc-1.67-1.67.0-r0.apk already provides cmd:grpc_cpp_plugin
  grpc-1.66-1.66.2-r0.apk disqualified because grpc-1.67-1.67.0-r0.apk already provides cmd:grpc_cpp_plugin
  grpc-1.66.2-r0.apk disqualified because grpc-1.67-1.67.0-r0.apk already provides cmd:grpc_cpp_plugin

This sets priority based on the minor version.

Related: https://github.com/wolfi-dev/os/pull/30459