Remove verbose flag for build

Remove the verbose flag from Go build command, since this doesn't produce helpful
output in almost all cases and is just slowing down the build slightly.

Makefile

@@ -7,7 +7,7 @@ PKG = ./pkg/...
 BIN ?= $(OUTPUT_DIR)/$(APP)
 KUBECTL_BIN ?= $(OUTPUT_DIR)/kubectl-$(APP)
 
-GO_FLAGS ?= -v -mod=vendor
+GO_FLAGS ?= -mod=vendor
 GO_TEST_FLAGS ?= -race -cover
 
 GO_PATH ?= $(shell go env GOPATH)