Adding milestone issue template inspired by the one present in the `p…

…m` repo (#1891)

.github/ISSUE_TEMPLATE/milestone.md

@@ -0,0 +1,41 @@
+---
+name: Milestone Issue Template
+about: Track Milestones
+title: "[Milestone] "
+labels: milestone
+assignees: ''
+
+---
+
+<!-- Please ensure you are assigning the matching epic label to the milestone -->
+<!-- All _active_ (being worked on) milestones MUST have an owner (GitHub assignee) -->
+
+**Planned start date**:
+**Due date**:
+
+# Summary
+
+# Acceptance Criteria
+
+<!-- describe the deliverable of this milestone and its attributes in plain English -->
+
+## Tasks
+
+<!--
+
+Breakdown of the work
+
+- [ ] Task 1
+- [ ] Link to GitHub issue tracking task 2
+
+-->
+
+# RAID (Risks, Assumptions, Issues and Dependencies)
+
+<!-- List dependencies on other milestones (avoid dependencies on tasks) -->
+
+<!-- List dependencies on other teams -->
+
+<!-- List any risks or assumptions that will be cleared as work progresses -->
+
+<!-- List any GitHub issues that tracks any blocker or any of the items above -->