fix: support double digit version numbers (#354)

Makefile

@@ -8,7 +8,7 @@ MODULE   = $(shell env GO111MODULE=on $(GO) list -m)
 DATE    ?= $(shell date +%FT%T%z)
 VERSION ?= $(shell git describe --tags --always --dirty --match=v* 2> /dev/null || \
 			cat $(CURDIR)/.version 2> /dev/null || echo v0)
-LATEST_RELEASE ?= $(shell git describe --tags --match=v* --abbrev=0 | grep -o "[0-9]\.[0-9]\.[0-9]")
+LATEST_RELEASE ?= $(shell git describe --tags --match=v* --abbrev=0 | grep -Eo "[0-9]+\.[0-9]+\.[0-9]+")
 PKGS     = $(or $(PKG),$(shell env GO111MODULE=on $(GO) list ./...))
 TESTPKGS = $(shell env GO111MODULE=on $(GO) list -f \
 			'{{ if or .TestGoFiles .XTestGoFiles }}{{ .ImportPath }}{{ end }}' \