Bump pkg:http (dev) dependency (dart-lang/markdown#551)

pkgs/markdown/CHANGELOG.md

diff --git a/pkgs/markdown/CHANGELOG.md b/pkgs/markdown/CHANGELOG.md
index 13f36ac..272702d 100644
--- a/pkgs/markdown/CHANGELOG.md
+++ b/pkgs/markdown/CHANGELOG.md
@@ -1,3 +1,5 @@
+## 7.1.2-wip
+
 ## 7.1.1
 
 * Fix delimiter row matching pattern for tables.

pkgs/markdown/lib/src/version.dart

diff --git a/pkgs/markdown/lib/src/version.dart b/pkgs/markdown/lib/src/version.dart
index 5d7be62..c8a2b00 100644
--- a/pkgs/markdown/lib/src/version.dart
+++ b/pkgs/markdown/lib/src/version.dart
@@ -1,2 +1,2 @@
 // Generated code. Do not modify.
-const packageVersion = '7.1.1';
+const packageVersion = '7.1.2-wip';

pkgs/markdown/pubspec.yaml

diff --git a/pkgs/markdown/pubspec.yaml b/pkgs/markdown/pubspec.yaml
index 886d996..387a667 100644
--- a/pkgs/markdown/pubspec.yaml
+++ b/pkgs/markdown/pubspec.yaml
@@ -1,5 +1,5 @@
 name: markdown
-version: 7.1.1
+version: 7.1.2-wip
 
 description: >-
   A portable Markdown library written in Dart that can parse Markdown into HTML.
@@ -24,7 +24,7 @@
   collection: ^1.15.0
   dart_flutter_team_lints: ^1.0.0
   html: ^0.15.0
-  http: ^0.13.5
+  http: '>=0.13.5 <2.0.0'
   io: ^1.0.0
   js: ^0.6.3
   path: ^1.8.0