fix(deps): pin dependencies

pubspec.yaml

@@ -19,26 +19,26 @@ environment:
 dependencies:
   flutter:
     sdk: flutter
-  fluro: ^1.4.0
-  package_info: ^0.4.0+3
-  intl: ^0.15.8
+  fluro: 1.7.8
+  package_info: 0.4.3
+  intl: 0.15.8
   url_launcher:
-  http: ^0.12.0+2
-  photo_view: ^0.3.0 # Newest version is 0.4.0, but it is not complicable with the SDK version.
-  firebase_core: ^0.4.0+6
+  http: 0.12.2
+  photo_view: 0.3.3 # Newest version is 0.4.0, but it is not complicable with the SDK version.
+  firebase_core: 0.4.5
 #  firebase_auth: ^0.11.1+6
-  cloud_firestore: ^0.12.5+2
-  firebase_messaging: ^5.0.4
-  shared_preferences: ^0.5.3+1
+  cloud_firestore: 0.12.11
+  firebase_messaging: 5.1.8
+  shared_preferences: 0.5.12
 
   # The following adds the Cupertino Icons font to your application.
   # Use with the CupertinoIcons class for iOS style icons.
-  cupertino_icons: ^0.1.2
+  cupertino_icons: 0.1.3
 
 dev_dependencies:
   flutter_test:
     sdk: flutter
-  image_test_utils: ^1.0.0
+  image_test_utils: 1.0.0
 
 # For information on the generic Dart part of this file, see the
 # following page: https://www.dartlang.org/tools/pub/pubspec