Add GRPC and protobuf SPM plugins to QPSBenchmark (#1475)

Motivation

We want to make use of both the protobuf and GRPC codegen SPM plugins in QPSBenchmark

Modifications

* Added support for both GRPC and protobuf plugin to QPSBenchmark

Result

QPSBenchmark now autogenerates both proto and GRPC code when building.

Author: gjcairo

Performance/QPSBenchmark/Makefile

@@ -35,7 +35,7 @@ let package = Package(
     ),
     .package(
       url: "https://github.com/apple/swift-protobuf.git",
-      from: "1.19.0"
+      from: "1.20.1"
     ),
   ],
   targets: [
@@ -53,14 +53,9 @@ let package = Package(
         .product(name: "SwiftProtobuf", package: "swift-protobuf"),
         .target(name: "BenchmarkUtils"),
       ],
-      exclude: [
-        "Model/benchmark_service.proto",
-        "Model/control.proto",
-        "Model/core_stats.proto",
-        "Model/messages.proto",
-        "Model/payloads.proto",
-        "Model/stats.proto",
-        "Model/worker_service.proto",
+      plugins: [
+        .plugin(name: "SwiftProtobufPlugin", package: "swift-protobuf"),
+        .plugin(name: "GRPCSwiftPlugin", package: "grpc-swift"),
       ]
     ),
     .target(

Performance/QPSBenchmark/Package.swift

@@ -5,8 +5,6 @@ An implementation of the QPS worker for benchmarking described in the
 
 ## Building
 
-To rebuild the proto files run `make generate-qps-worker`.
-
 The benchmarks can be built in the usual Swift Package Manager way but release
 mode is strongly recommended: `swift build -c release`