Update pubspec

pubspec.lock

@@ -214,6 +214,13 @@ packages:
       url: "https://pub.dartlang.org"
     source: hosted
     version: "0.14.0+3"
+  http:
+    dependency: "direct main"
+    description:
+      name: http
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "0.12.2"
   http_multi_server:
     dependency: transitive
     description:

pubspec.yaml

@@ -18,14 +18,14 @@ publish_to: 'none' # Remove this line if you wish to publish to pub.dev
 version: 1.0.0+1
 
 environment:
-  sdk: ">=2.7.0 <3.0.0"
+  sdk: '>=2.7.0 <3.0.0'
 
 dependencies:
   json_annotation: ^3.0.1
+  http: ^0.12.2
   flutter:
     sdk: flutter
 
-
   # The following adds the Cupertino Icons font to your application.
   # Use with the CupertinoIcons class for iOS style icons.
   cupertino_icons: ^0.1.3
@@ -41,23 +41,18 @@ dev_dependencies:
 
 # The following section is specific to Flutter.
 flutter:
-
   # The following line ensures that the Material Icons font is
   # included with your application, so that you can use the icons in
   # the material Icons class.
   uses-material-design: true
-
   # To add assets to your application, add an assets section, like this:
   # assets:
   #   - images/a_dot_burr.jpeg
   #   - images/a_dot_ham.jpeg
-
   # An image asset can refer to one or more resolution-specific "variants", see
   # https://flutter.dev/assets-and-images/#resolution-aware.
-
   # For details regarding adding assets from package dependencies, see
   # https://flutter.dev/assets-and-images/#from-packages
-
   # To add custom fonts to your application, add a fonts section here,
   # in this "flutter" section. Each entry in this list should have a
   # "family" key with the font family name, and a "fonts" key with a