update sdk constraint to <3.0.0 (#905)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 2c85740..a1a4d3b 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -3,6 +3,7 @@
 * When using `--precompiled`, the test runner now allows symlinks to reach
   outside the precompiled directory. This allows more efficient creation of
   precompiled directories (using symlinks instead of copies).
+* Updated max sdk range to `<3.0.0`.
 
 ## 1.2.0
 
diff --git a/pubspec.yaml b/pubspec.yaml
index 309ef6c..6bcfa56 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -4,7 +4,7 @@
 description: A library for writing dart unit tests.
 homepage: https://github.com/dart-lang/test
 environment:
-  sdk: '>=2.0.0-dev.54.0 <2.0.0'
+  sdk: '>=2.0.0-dev.54.0 <3.0.0'
 dependencies:
   analyzer: '>=0.26.4 <0.33.0'
   args: '>=1.4.0 <2.0.0'