Updated dependencies (#255)

* Bump android compile and target version, also flutter dependencies and resolve issues

* Remove deprecated splashscreen and added support for new Android 12 version.

* Updated workflow action versions and flutter sdk

* Resolved linting issues

* Resolved test binding issues

lib/widget/fields.dart

@@ -80,7 +80,7 @@ class FilePickerDialog {
     actions.add(
       SimpleDialogOption(
         child: ListTile(
-          leading: FaIcon(FontAwesomeIcons.fileUpload),
+          leading: FaIcon(FontAwesomeIcons.fileArrowUp),
           title: Text(allowFiles ? L10().selectFile : L10().selectImage),
         ),
         onPressed: () async {