update Makefile (#123)

Makefile

@@ -7,7 +7,7 @@ COMMIT := $(shell git log -1 --format='%H')
 
 # don't override user values
 ifeq (,$(VERSION))
-  VERSION := $(shell git describe --exact-match 2>/dev/null)
+  VERSION := $(shell git describe --tags --exact-match 2>/dev/null)
   # if VERSION is empty, then populate it with branch's name and raw commit hash
   ifeq (,$(VERSION))
     VERSION := $(BRANCH)-$(COMMIT)
@@ -22,7 +22,7 @@ DOCKER := $(shell which docker)
 BUILDDIR ?= $(CURDIR)/build
 
 GO_SYSTEM_VERSION = $(shell go version | cut -c 14- | cut -d' ' -f1 | cut -d'.' -f1-2)
-REQUIRE_GO_VERSION = 1.20
+REQUIRE_GO_VERSION = 1.21
 
 export GO111MODULE = on