Getting a DatabaseException on startup: (database is locked (code 5 SQLITE_BUSY[5]))

## 🐛 Bug Report

Hi, I'm having a DatabaseException on the application's first load, when it tries to setup the database for the cache. The cache stays unusable for this first load, but the second time the application is opened it can work this out and then it will continue working every time.

This is a logcat output from Android:

```
09-05 16:18:26.154 19280 19371 I flutter : error DatabaseException(database is locked (code 5 SQLITE_BUSY[5])) sql 'BEGIN EXCLUSIVE' args [] during open, closing...
09-05 16:18:26.165 19280 19371 E flutter : [ERROR:flutter/runtime/dart_vm_initializer.cc(41)] Unhandled Exception: DatabaseException(database is locked (code 5 SQLITE_BUSY[5])) sql 'BEGIN EXCLUSIVE' args []
09-05 16:18:26.165 19280 19371 E flutter : #0 wrapDatabaseException (package:sqflite/src/exception_impl.dart:11)
09-05 16:18:26.165 19280 19371 E flutter :
09-05 16:18:26.165 19280 19371 E flutter : #1 SqfliteDatabaseMixin.txnSynchronized (package:sqflite_common/src/database_mixin.dart:465)
09-05 16:18:26.165 19280 19371 E flutter :
09-05 16:18:26.165 19280 19371 E flutter : #2 SqfliteDatabaseMixinExt.txnBeginTransaction (package:sqflite_common/src/database_mixin.dart:353)
09-05 16:18:26.165 19280 19371 E flutter :
09-05 16:18:26.165 19280 19371 E flutter : #3 SqfliteDatabaseMixin.beginTransaction (package:sqflite_common/src/database_mixin.dart:719)
09-05 16:18:26.165 19280 19371 E flutter :
09-05 16:18:26.165 19280 19371 E flutter : #4 SqfliteDatabaseMixinExt._txnTransaction (package:sqflite_common/src/database_mixin.dart:330)
09-05 16:18:26.165 19280 19371 E flutter :
09-05 16:18:26.165 19280 19371 E flutter : #5 BasicLock.synchronized (package:synchronized/src/basic_lock.dart:33)
09-05 16:18:26.165 19280 19371 E flutter :
09-05 16:18:26.165 19280 19371 E flutter : #6 SqfliteDatabaseMixin.txnSynchronized (package:sqflite_common/src/database_mixin.dart:490)
09-05 16:18:26.165 19280 19371 E flutter :
09-05 16:18:26.165 19280 19371 E flutter : #7 SqfliteDatabaseMixin.doOpen (package:sqflite_common/src/database_mixin.dart:939)
09-05 16:18:26.165 19280 19371 E flutter :
09-05 16:18:26.165 19280 19371 E flutter : #8 SqfliteDatabaseOpenHelper.openDatabase (package:sqflite_common/src/database.dart:46)
09-05 16:18:26.165 19280 19371 E flutter :
09-05 16:18:26.165 19280 19371 E flutter : #9 SqfliteDatabaseFactoryMixin.openDatabase. (package:sqflite_common/src/factory_mixin.dart:110)
09-05 16:18:26.165 19280 19371 E flutter :
09-05 16:18:26.165 19280 19371 E flutter : #10 ReentrantLock.synchronized. (package:synchronized/src/reentrant_lock.dart:37)
09-05 16:18:26.165 19280 19371 E flutter :
09-05 16:18:26.165 19280 19371 E flutter : #11 BasicLock.synchronized (package:synchronized/src/basic_lock.dart:33)
09-05 16:18:26.165 19280 19371 E flutter :
09-05 16:18:26.165 19280 19371 E flutter : #12 CacheObjectProvider.open (package:flutter_cache_manager/src/storage/cache_info_repositories/cache_object_provider.dart:30)
09-05 16:18:26.165 19280 19371 E flutter :
09-05 16:18:26.165 19280 19371 E flutter : #13 CacheStore._getCacheDataFromDatabase (package:flutter_cache_manager/src/cache_store.dart:112)
09-05 16:18:26.165 19280 19371 E flutter :
```

At the moment I only tried this on Android, and I'm using version 3.3.1.

My first guess is that some other library may be using Sqlite at the same time, or some other thing like that, but anyways that doesn't seems to be a good reason to crash. Is this issue known?

Thank you

在 Android 上使用 3.3.1 版本重现首次加载失败，然后从 package:flutter_cache_manager/src/storage/cache_info_repositories/cache_object_provider.dart 中的 CacheObjectProvider.open 和 cache_store.dart 中的 CacheStore._getCacheDataFromDatabase 开始。跟踪 BEGIN EXCLUSIVE 经过 sqflite 的路径，并确定缓存数据库在启动期间被锁定的原因；当首次加载能够在没有未处理的 SQLITE_BUSY 异常的情况下打开缓存时，即表示完成。

由索引模型根据 Issue 内容生成。