Upgrade package:intl to 0.20.2 (#162591)

Run `flutter update-packages --cherry-pick-package intl
--cherry-pick-version 0.20.2`

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examples/api/pubspec.yaml

@@ -51,7 +51,7 @@ dev_dependencies:
   glob: 2.1.3 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
   http_multi_server: 3.2.2 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
   http_parser: 4.1.2 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
-  intl: 0.19.0 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  intl: 0.20.2 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
   io: 1.0.5 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
   js: 0.7.1 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
   leak_tracker: 10.0.9 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
@@ -94,4 +94,4 @@ dev_dependencies:
 flutter:
   uses-material-design: true
 
-# PUBSPEC CHECKSUM: 9810
+# PUBSPEC CHECKSUM: 980a