Repair sonar scanner that was broken by the change version script

Change-Id: I15dcd88587012def0db018c5aa7ebcc4427596d9
diff --git a/tools/build/onos-prepare-sonar b/tools/build/onos-prepare-sonar
index 293f5e9..1520d9c 100755
--- a/tools/build/onos-prepare-sonar
+++ b/tools/build/onos-prepare-sonar
@@ -253,7 +253,7 @@
     with open(bazel_vars_path, 'r') as bazel_vars_file:
         for bazel_var in bazel_vars_file.readlines():
             if "ONOS_VERSION" in bazel_var:
-                return bazel_var.replace(" ", "").replace('ONOS_VERSION='2.1.0-SNAPSHOT'
+                return bazel_var.replace(" ", "").replace('ONOS_VERSION="', '').replace('"', '')
 
 
 def _main():