stable null safety release (dart-lang/pub_semver#54)

pkgs/pub_semver/CHANGELOG.md

diff --git a/pkgs/pub_semver/CHANGELOG.md b/pkgs/pub_semver/CHANGELOG.md
index 3719707..5140fe2 100644
--- a/pkgs/pub_semver/CHANGELOG.md
+++ b/pkgs/pub_semver/CHANGELOG.md
@@ -1,3 +1,7 @@
+# 2.0.0
+
+- Stable null safety release.
+
 # 2.0.0-nullsafety.0
 
 - Migrate to null safety.

pkgs/pub_semver/pubspec.yaml

diff --git a/pkgs/pub_semver/pubspec.yaml b/pkgs/pub_semver/pubspec.yaml
index dc2d6ac..f628d38 100644
--- a/pkgs/pub_semver/pubspec.yaml
+++ b/pkgs/pub_semver/pubspec.yaml
@@ -1,5 +1,5 @@
 name: pub_semver
-version: 2.0.0-nullsafety.0
+version: 2.0.0
 description: >-
  Versions and version constraints implementing pub's versioning policy. This
  is very similar to vanilla semver, with a few corner cases.
@@ -9,10 +9,7 @@
  sdk: '>=2.12.0-0 <3.0.0'
 
 dependencies:
-  collection: ^1.15.0-nullsafety.2
+  collection: ^1.15.0
 
 dev_dependencies:
   test: ^1.16.0-nullsafety.1
-
-dependency_overrides:
-  analyzer: any