Update dependency freezed to ^0.15.0 (#94)

Co-authored-by: Renovate Bot <[email protected]>
Co-authored-by: Daichi Furiya <[email protected]>

Author: 3 people

pubspec.yaml

@@ -68,7 +68,7 @@ dev_dependencies:
   auto_route_generator: ^3.0.1
 
   # For Model
-  freezed: ^0.14.2
+  freezed: ^0.15.0
 
   # For Analyzer
   flutter_lints: ^1.0.4