don't set dbName to null when db close() is called

Author: buenaflor

sqflite/lib/src/sentry_database.dart

@@ -44,7 +44,7 @@ class SentryDatabase extends SentryDatabaseExecutor implements Database {
   static const dbNameKey = 'db.name';
   @internal
   // ignore: public_member_api_docs
-  String? dbName;
+  String dbName;
 
   /// ```dart
   /// import 'package:sqflite/sqflite.dart';
@@ -82,7 +82,6 @@ class SentryDatabase extends SentryDatabaseExecutor implements Database {
       try {
         await _database.close();
 
-        dbName = null;
         span?.status = SpanStatus.ok();
       } catch (exception) {
         span?.throwable = exception;

sqflite/test/sentry_database_test.dart

@@ -63,8 +63,6 @@ void main() {
 
       await db.close();
 
-      expect(db.dbName, null);
-
       final span = fixture.tracer.children.last;
       expect(span.context.operation, 'db');
       expect(span.context.description, 'Close DB: $inMemoryDatabasePath');
@@ -163,8 +161,6 @@ void main() {
       expect(db.dbName, inMemoryDatabasePath);
 
       await db.close();
-
-      expect(db.dbName, null);
     });
 
     tearDown(() {