Update feature request issue template label

I updated the label's name from "feature" to "feature request" to make
it more descriptive in GitHub, and that broke this template.

.github/ISSUE_TEMPLATE/feature_request.yml

@@ -1,6 +1,6 @@
 name: Feature suggestion
 description: Propose a feature in the Pocket Casts Android app
-labels: ["feature", "triage"]
+labels: ["feature request", "triage"]
 body:
 
  - type: markdown