Add issue template and other fixes

Author: mosuem

.github/ISSUE_TEMPLATE/pool.md

@@ -0,0 +1,5 @@
+---
+name: "package:pool"
+about: "Create a bug or file a feature request against package:pool."
+labels: "package:pool"
+---

pkgs/pool/pubspec.yaml

@@ -3,7 +3,7 @@ version: 1.5.2-wip
 description: >-
   Manage a finite pool of resources.
   Useful for controlling concurrent file system or network requests.
-repository: https://github.com/dart-lang/pool
+repository: https://github.com/dart-lang/tools/tree/main/pkgs/pool
 
 environment:
   sdk: ^3.4.0