Replace 'pub' with 'dart pub' in CI scripts (#401)

Bare use of 'pub' is deprecated.

Also updates the pinned repo tool version, since some uses of 'pub' have
been fixed there.
diff --git a/.cirrus.yml b/.cirrus.yml
index 18996d2..a73d33e 100644
--- a/.cirrus.yml
+++ b/.cirrus.yml
@@ -8,7 +8,7 @@
     - git fetch origin master # To set FETCH_HEAD for "git merge-base" to work
     # Pinned version of the plugin tools, to avoid breakage in this repository
     # when pushing updates from flutter/plugins.
-    - pub global activate flutter_plugin_tools 0.1.4
+    - dart pub global activate flutter_plugin_tools 0.3.0
 
 flutter_upgrade_template: &FLUTTER_UPGRADE_TEMPLATE
   upgrade_flutter_script:
@@ -31,7 +31,7 @@
   matrix:
     - name: format+analyze
       format_script: ./script/tool_runner.sh format --fail-on-change --clang-format=clang-format-5.0
-      license_script: pub global run flutter_plugin_tools license-check
+      license_script: dart pub global run flutter_plugin_tools license-check
       analyze_script: ./script/tool_runner.sh analyze --custom-analysis=web_benchmarks/testing/test_app,flutter_lints/example
       pubspec_script: ./script/tool_runner.sh pubspec-check
     - name: publishable
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 19decff..539b232 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -25,7 +25,7 @@
       with:
         fetch-depth: 0 # Fetch all history so the tool can get all the tags to determine version.
     - name: Set up tools
-      run: pub global activate flutter_plugin_tools 0.3.0
+      run: dart pub global activate flutter_plugin_tools 0.3.0
 
     # # This workflow should be the last to run. So wait for all the other tests to succeed.
     - name: Wait on all tests
diff --git a/script/tool_runner.sh b/script/tool_runner.sh
index c0a8fd0..11c79cc 100755
--- a/script/tool_runner.sh
+++ b/script/tool_runner.sh
@@ -16,7 +16,7 @@
 BRANCH_NAME="${BRANCH_NAME:-"$(git rev-parse --abbrev-ref HEAD)"}"
 if [[ "${BRANCH_NAME}" == "master" ]]; then
   echo "Running for all packages"
-  (cd "$REPO_DIR" && pub global run flutter_plugin_tools "${ACTIONS[@]}" $BUILD_SHARDING)
+  (cd "$REPO_DIR" && dart pub global run flutter_plugin_tools "${ACTIONS[@]}" $BUILD_SHARDING)
 else
-  (cd "$REPO_DIR" && pub global run flutter_plugin_tools "${ACTIONS[@]}" --run-on-changed-packages $BUILD_SHARDING)
+  (cd "$REPO_DIR" && dart pub global run flutter_plugin_tools "${ACTIONS[@]}" --run-on-changed-packages $BUILD_SHARDING)
 fi