all: fix Github Workflow for tests, drop Travis

_tutorial/wire.go

@@ -12,7 +12,8 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-//+build wireinject
+//go:build wireinject
+// +build wireinject
 
 // The build tag makes sure the stub is not built in the final build.
 package main

_tutorial/wire_gen.go

@@ -1,7 +1,8 @@
 // Code generated by Wire. DO NOT EDIT.
 
 //go:generate go run github.com/google/wire/cmd/wire
-//+build !wireinject
+//go:build !wireinject
+// +build !wireinject
 
 package main