[YUNIKORN-1885] Update Go version filter (#101)

The Go version filter pulls in patch release details which shows errors
when running tests with pre-release (release candidate) go version to
check for compatibility.

Closes: #101

Signed-off-by: Craig Condit <ccondit@apache.org>
diff --git a/Makefile b/Makefile
index e7ed5c0..f604242 100644
--- a/Makefile
+++ b/Makefile
@@ -18,7 +18,7 @@
 
 # Check if this GO tools version used is at least the version of go specified in
 # the go.mod file. The version in go.mod should be in sync with other repos.
-GO_VERSION := $(shell go version | awk '{print substr($$3, 3, 10)}')
+GO_VERSION := $(shell go version | awk '{print substr($$3, 3, 4)}')
 MOD_VERSION := $(shell cat .go_version) 
 
 GM := $(word 1,$(subst ., ,$(GO_VERSION)))