fix(helm): Correct and improve resilence of template check in unit test (#5010)

Make the current check for the number of templates on create more
resilient by using a varible to store the expected number
of templates. In addition, fix the error message so that it displays
the correct number expected of templates.

Closes #5009
Signed-off-by: Henry Nash <henry.nash@uk.ibm.com>

cmd/helm/create_test.go

@@ -143,8 +143,9 @@ func TestCreateStarterCmd(t *testing.T) {
 		t.Errorf("Wrong API version: %q", c.Metadata.ApiVersion)
 	}
 
-	if l := len(c.Templates); l != 7 {
-		t.Errorf("Expected 6 templates, got %d", l)
+	expectedTemplateCount := 7
+	if l := len(c.Templates); l != expectedTemplateCount {
+		t.Errorf("Expected %d templates, got %d", expectedTemplateCount, l)
 	}
 
 	found := false