update ci; prep for publishing (#30)

diff --git a/.github/dependabot.yml b/.github/dependabot.yml
index 40cab31..2144819 100644
--- a/.github/dependabot.yml
+++ b/.github/dependabot.yml
@@ -1,11 +1,8 @@
-# Set update schedule for GitHub Actions
-# See https://docs.github.com/en/code-security/supply-chain-security/keeping-your-dependencies-updated-automatically/keeping-your-actions-up-to-date-with-dependabot
-
+# Dependabot configuration file.
 version: 2
-updates:
 
-- package-ecosystem: "github-actions"
-  directory: "/"
-  schedule:
-    # Check for updates to GitHub Actions every weekday
-    interval: "monthly"
+updates:
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    schedule:
+      interval: "monthly"
diff --git a/.github/workflows/test-package.yml b/.github/workflows/test-package.yml
index 55569bc..664394e 100644
--- a/.github/workflows/test-package.yml
+++ b/.github/workflows/test-package.yml
@@ -22,8 +22,8 @@
       matrix:
         sdk: [dev]
     steps:
-      - uses: actions/checkout@v3
-      - uses: dart-lang/setup-dart@v1
+      - uses: actions/checkout@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8
+      - uses: dart-lang/setup-dart@6a218f2413a3e78e9087f638a238f6b40893203d
         with:
           sdk: ${{ matrix.sdk }}
       - id: install
@@ -49,8 +49,8 @@
         os: [ubuntu-latest]
         sdk: [2.12.0, dev]
     steps:
-      - uses: actions/checkout@v3
-      - uses: dart-lang/setup-dart@v1
+      - uses: actions/checkout@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8
+      - uses: dart-lang/setup-dart@6a218f2413a3e78e9087f638a238f6b40893203d
         with:
           sdk: ${{ matrix.sdk }}
       - id: install
diff --git a/CHANGELOG.md b/CHANGELOG.md
index e849917..a7202cd 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,4 +1,4 @@
-## 2.1.1-dev
+## 2.1.1
 
 * Populate the pubspec `repository` field.
 * Switch to using `package:lints`.
diff --git a/pubspec.yaml b/pubspec.yaml
index e769a84..3849230 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,5 +1,5 @@
 name: source_map_stack_trace
-version: 2.1.1-dev
+version: 2.1.1
 description: A package for applying source maps to stack traces.
 repository: https://github.com/dart-lang/source_map_stack_trace