Update operator version in Makefile

Now the version in the Makefile matches the version of the operator

Makefile

@@ -5,7 +5,7 @@ export MAIN_BRANCH ?= main
 # To re-generate a bundle for another specific version without changing the standard setup, you can:
 # - use the VERSION as arg of the bundle target (e.g make bundle VERSION=0.0.2)
 # - use environment variables to overwrite this value (e.g export VERSION=0.0.2)
-VERSION ?= 1.6.0
+VERSION ?= 1.8.0
 
 # CHANNELS define the bundle channels used in the bundle.
 # Add a new line here if you would like to change its default config. (E.g CHANNELS = "candidate,fast,stable")