Apply suggestions from code review

Author: glbrntt

Sources/GRPCCore/Documentation.docc/Tutorials/Hello-World/Hello-World.tutorial

@@ -34,7 +34,7 @@
     The remainder of this tutorial assumes you installed `protoc` and it's available in
     your `$PATH`.
 
-    You may notices that the `swift` commands are all prefixed with `PROTOC_PATH=$(which protoc)`,
+    You may notice that the `swift` commands are all prefixed with `PROTOC_PATH=$(which protoc)`,
     this is to let the build system know where `protoc` is located so that it can generate stubs
     for you. You can read more about it in the  [gRPC Swift Protobuf
     documentation](https://swiftpackageindex.com/grpc/grpc-swift-protobuf/documentation/grpcprotobuf/generating-stubs).

Sources/GRPCCore/Documentation.docc/Tutorials/Route-Guide/Route-Guide.tutorial

@@ -26,7 +26,7 @@
     The remainder of this tutorial assumes you installed `protoc` and it's available in
     your `$PATH`.
 
-    You may notices that the `swift` commands are all prefixed with `PROTOC_PATH=$(which protoc)`,
+    You may notice that the `swift` commands are all prefixed with `PROTOC_PATH=$(which protoc)`,
     this is to let the build system know where `protoc` is located so that it can generate stubs
     for you. You can read more about it in the  [gRPC Swift Protobuf
     documentation](https://swiftpackageindex.com/grpc/grpc-swift-protobuf/documentation/grpcprotobuf/generating-stubs).