chore: add ui icons package to enhancement template (#11344)

**Related Issue:** #9922

## Summary
Adds the icons package to the enhancement issue template.

Author: geospatialem

.github/ISSUE_TEMPLATE/enhancement.yml

@@ -66,6 +66,7 @@ body:
         - label: "@esri/calcite-components"
         - label: "@esri/calcite-components-react"
         - label: "@esri/calcite-design-tokens"
+        - label: "@esri/calcite-ui-icons"
         - label: "@esri/eslint-plugin-calcite-components"
   - type: dropdown
     id: esri-team