Prepare to publish (#524)

- Fix changelog version and remove wording about the allow list which
  does not apply anymore.
- Drop overrides on `test` and `http_parser`. Add dev dependency and
  override on `shelf` which is the sole cause of an impossible solve.
  This will be resolved once shelf is published and `test` allows it.

Author: natebosch

CHANGELOG.md

@@ -1,17 +1,9 @@
-## 0.13.0-nullsafety-dev
-
-Pre-release for the null safety migration of this package.
-
-Note that 0.12.3 may not be the final stable null safety release version, we
-reserve the right to release it as a 0.13.0 breaking change.
-
-This release will be pinned to only allow pre-release sdk versions starting from
-2.10.0-2.0.dev, which is the first version where this package will appear in the
-null safety allow list.
+## 0.13.0-nullsafety.0
 
+* Migrate to null safety.
 * Add `const` constructor to `ByteStream`.
 * Migrate `BrowserClient` from `blob` to `arraybuffer`.
-* **BREAKING** All APIs which previously allowed a `String` or `Uri` to be
+* **Breaking** All APIs which previously allowed a `String` or `Uri` to be
   passed now require a `Uri`.
 * **Breaking** Added a `body` and `encoding` argument to `Client.delete`. This
   is only breaking for implementations which override that method.

pubspec.yaml

@@ -13,9 +13,9 @@ dependencies:
   pedantic: ^1.10.0-nullsafety
 
 dev_dependencies:
+  shelf: any
   test: ^1.16.0-nullsafety.4
 
 dependency_overrides:
-  http_parser: ^4.0.0-nullsafety
-  # Because pkg:test does not support pkg:http ^0.13.0
-  test: ^1.16.0-nullsafety.5
+  shelf:
+    git: git://github.com/dart-lang/shelf.git