Create Upgrade_Toolkit.md

Author: dipeshrath

cd3_automation_toolkit/documentation/user_guide/Upgrade_Toolkit.md

@@ -0,0 +1,13 @@
+# Steps to Upgrade Your Toolkit (For Existing Customers):
+
+## Release v10
+1. Build new image using the latest code from main branch.
+1. Launch a new container using the same outdir.
+1. Use new excel sheet templates to use OKE and SCH.
+1. For existing services, user can continue using existing outdir.
+
+<br><br>
+<div align='center'>
+
+| <a href="/cd3_automation_toolkit/documentation/user_guide/FAQ.md">:arrow_backward: Prev</a> | <a href="/README.md#table-of-contents-bookmark">Next :arrow_forward:</a> |
+| :---- | -------: |