ci: add Feature Request issue template

.gitlab/issue_templates/Feature Request.md

@@ -0,0 +1,20 @@
+## Summary
+
+<!-- What feature are you requesting? -->
+
+## Motivation
+
+<!-- Why is this needed? What problem does it solve? -->
+
+## Proposed Solution
+
+<!-- How do you envision this being implemented? -->
+
+## Alternatives Considered
+
+<!-- Have you considered alternative approaches? -->
+
+## Additional Context
+
+/label ~enhancement
+