CLOUD-956 Modify labels in feature request template (#2301)

Updated labels for feature request issue template.

Author: hors

.github/ISSUE_TEMPLATE/1-feature-request.yml

@@ -1,6 +1,6 @@
 name: Feature request 🧭
 description: Suggest an idea for this project
-labels: "feature-request"
+labels: ["feature-request", "Proposed", "PSMDB", "MongoDB"]
 body:
 - type: textarea
   attributes: