Add debugging

Makefile
--------
  o Augment mod-update target to depend on go-version.
  o go-version: Display/log interpreter version for running jobs.
  o Sridhar has a job failure that may be version dependent.

Change-Id: Ie5c512ca2f7ca71ec6bd99b962ef6ebb4a6fbf41
diff --git a/Makefile b/Makefile
index d9bdc16..423323e 100644
--- a/Makefile
+++ b/Makefile
@@ -75,7 +75,15 @@
 ## -----------------------------------------------------------------------
 ## -----------------------------------------------------------------------
 .PHONY: mod-update
-mod-update: mod-tidy mod-vendor
+mod-update: go-version mod-tidy mod-vendor
+
+## -----------------------------------------------------------------------
+## -----------------------------------------------------------------------
+.PHONY: go-version
+go-version :
+	$(call banner-enter,Target $@)
+	${GO} version
+	$(call banner-leave,Target $@)
 
 ## -----------------------------------------------------------------------
 ## -----------------------------------------------------------------------