chore: set max SDK version to <3.0.0 (#27)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index e621d98..e11570b 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,7 @@
+## 1.0.9
+
+* Set max SDK version to `<3.0.0`.
+
 ## 1.0.8
 
 * Remove use of deprecated constant name.
diff --git a/analysis_options.yaml b/analysis_options.yaml
deleted file mode 100644
index a10d4c5..0000000
--- a/analysis_options.yaml
+++ /dev/null
@@ -1,2 +0,0 @@
-analyzer:
-  strong-mode: true
diff --git a/pubspec.yaml b/pubspec.yaml
index 86236b7..6345dfe 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,16 +1,17 @@
 name: web_socket_channel
-version: 1.0.8
+version: 1.0.9
+
 description: StreamChannel wrappers for WebSockets.
 author: Dart Team <misc@dartlang.org>
 homepage: https://github.com/dart-lang/web_socket_channel
 
 environment:
-  sdk: '>=2.0.0-dev.23.0 <2.0.0'
+  sdk: '>=2.0.0-dev.23.0 <3.0.0'
 
 dependencies:
   async: '>=1.3.0 <3.0.0'
   crypto: '>=0.9.2 <3.0.0'
-  stream_channel: '^1.2.0'
+  stream_channel: ^1.2.0
 
 dev_dependencies:
   test: ^1.2.0