add MR template

.gitlab/merge_request_templates/default.md

+## Type of change
+- [ ] Bug Fix 
+- [ ] Feature
+
+**Please provide link to gitlab issue or ADR(Architecture Decision Record)**  
+
+## Does this introduce a change in the core logic?
+- [YES/NO]
+
+## Does this introduce a change in the cloud provider implementation, if so which cloud?
+- [ ] AWS 
+- [ ] Azure
+- [ ] GCP
+- [ ] IBM
+
+## Does this introduce a breaking change?
+- [YES/NO]
+
+## What is the current behavior?
+
+## What is the new/expected behavior?
+
+## Have you added/updated Unit Tests and Integration Tests?
+
+## Any other useful information