deps: Upgrade flutter_local_notifications to the latest

(The related flutter_local_notifications_platform_interface plugin is also
upgraded to the latest.)

After the Flutter upstream commit:
  flutter/flutter@f23dbc5
a build error related to flutter_local_notifications plugin occurs when
trying to run the app on Android. The upgrade to flutter_local_notifications ^7.2.0
version resolves the issue.

More about the issue:
  MaikuB/flutter_local_notifications#2329

Fixes: zulip#771

pubspec.lock

@@ -444,10 +444,10 @@ packages:
     dependency: "direct main"
     description:
       name: flutter_local_notifications
-      sha256: "40e6fbd2da7dcc7ed78432c5cdab1559674b4af035fddbfb2f9a8f9c2112fcef"
+      sha256: ced76d337f54de33d7d9f06092137b4ac2da5079e00cee8a11a1794ffc7c61c6
       url: "https://pub.dev"
     source: hosted
-    version: "17.1.2"
+    version: "17.2.1"
   flutter_local_notifications_linux:
     dependency: transitive
     description:
@@ -460,10 +460,10 @@ packages:
     dependency: "direct main"
     description:
       name: flutter_local_notifications_platform_interface
-      sha256: "340abf67df238f7f0ef58f4a26d2a83e1ab74c77ab03cd2b2d5018ac64db30b7"
+      sha256: "85f8d07fe708c1bdcf45037f2c0109753b26ae077e9d9e899d55971711a4ea66"
       url: "https://pub.dev"
     source: hosted
-    version: "7.1.0"
+    version: "7.2.0"
   flutter_localizations:
     dependency: "direct main"
     description: flutter

pubspec.yaml

@@ -47,8 +47,8 @@ dependencies:
   firebase_core: ^3.1.0
   firebase_messaging: ^15.0.1
   flutter_color_models: ^1.3.3+2
-  flutter_local_notifications: ^17.0.0
-  flutter_local_notifications_platform_interface: ^7.0.0+1
+  flutter_local_notifications: ^17.2.1
+  flutter_local_notifications_platform_interface: ^7.2.0
   html: ^0.15.1
   http: ^1.0.0
   image_picker: ^1.0.0