Fix license checks GOTOOLCHAIN setting

Author: josvazg

Makefile

@@ -163,6 +163,7 @@ build-licenses.csv: go.mod ## Track licenses in a CSV file
 	@echo "========================================"
 	export GOOS=linux
 	export GOARCH=amd64
+	export GOTOOLCHAIN=local
 	go run github.com/google/$(GO_LICENSES)@v$(GO_LICENSES_VERSION) csv --include_tests $(BASE_GO_PACKAGE)/... > licenses.csv
 	echo $(GOMOD_SHA) > $(LICENSES_GOMOD_SHA_FILE)
 
@@ -182,6 +183,7 @@ check-licenses: licenses-up-to-date ## Check licenses are compliant with our res
 	@echo "============================================"
 	export GOOS=linux
 	export GOARCH=amd64
+	export GOTOOLCHAIN=local
 	go run github.com/google/$(GO_LICENSES)@v$(GO_LICENSES_VERSION) check --include_tests \
 	--disallowed_types $(DISALLOWED_LICENSES) $(BASE_GO_PACKAGE)/...
 	@echo "--------------------"