remove outdated notice in makefile (go-gitea#14720)

Co-authored-by: 6543 <[email protected]>

Makefile

@@ -573,7 +573,6 @@ release-windows: | $(DIST_DIRS)
 	@hash xgo > /dev/null 2>&1; if [ $$? -ne 0 ]; then \
 		GO111MODULE=off $(GO) get -u src.techknowlogick.com/xgo; \
 	fi
-	@echo "Warning: windows version is built using golang 1.14"
 	CGO_CFLAGS="$(CGO_CFLAGS)" GO111MODULE=off xgo -go $(XGO_VERSION) -buildmode exe -dest $(DIST)/binaries -tags 'netgo osusergo $(TAGS)' -ldflags '-linkmode external -extldflags "-static" $(LDFLAGS)' -targets 'windows/*' -out gitea-$(VERSION) .
 ifeq ($(CI),drone)
 	cp /build/* $(DIST)/binaries