tests/operator: define usesSha as a static function

usesSha() is a single static function. Defining it as a named lambda
needlessly adds mental burden, as the read need to keep in mind that it
may change in the future.

With this change, there is no need to declare usesSha in one place, and
define it elsewhere, and indentation level is reduced.

Signed-off-by: Dan Kenigsberg <[email protected]>

tests/operator/operator.go

@@ -153,7 +153,6 @@ var _ = Describe("[Serial][sig-operator]Operator", Serial, decorators.SigOperato
 		deleteOperator                         func(string)
 		deleteTestingManifests                 func(string)
 		deleteAllKvAndWait                     func(bool)
-		usesSha                                func(string) bool
 		ensureShasums                          func()
 		getVirtLauncherSha                     func() string
 		generatePreviousVersionVmYamls         func(string, string)
@@ -674,10 +673,6 @@ var _ = Describe("[Serial][sig-operator]Operator", Serial, decorators.SigOperato
 
 		}
 
-		usesSha = func(image string) bool {
-			return strings.Contains(image, "@sha256:")
-		}
-
 		ensureShasums = func() {
 			if flags.SkipShasumCheck {
 				log.Log.Warning("Cannot use shasums, skipping")
@@ -3481,3 +3476,7 @@ func nodeSelectorExistInDeployment(virtClient kubecli.KubevirtClient, deployment
 	}
 	return true
 }
+
+func usesSha(image string) bool {
+	return strings.Contains(image, "@sha256:")
+}