update spgw image in omec-control-plane

spgw changes to delete gauge counters if value is 0

Change-Id: I29f4e6900a9138cbf3e2774c3d60d2d88b51e7a0
diff --git a/omec-control-plane/Chart.yaml b/omec-control-plane/Chart.yaml
index 5af9a6e..ec6fae5 100644
--- a/omec-control-plane/Chart.yaml
+++ b/omec-control-plane/Chart.yaml
@@ -10,4 +10,4 @@
 name: omec-control-plane
 icon: https://guide.opencord.org/logos/cord.svg
 
-version: 0.9.17
+version: 0.9.18