**poco 初始化报错** cannot use a string pattern on a bytes-like object

**描述问题bug**
使用AndroidUiautomationPoco初始化错误。

```
Traceback (most recent call last):
File "/Users/HGI/Program/projects/appCrawl/main.py", line 8, in
poco = AndroidUiautomationPoco(screenshot_each_action=False)
File "/Users/HGI/Program/env3/lib/python3.8/site-packages/poco/drivers/android/uiautomation.py", line 170, in __init__
self.ime.start()
File "/Users/HGI/Program/env3/lib/python3.8/site-packages/airtest/core/android/ime.py", line 77, in start
self.adb.shell("ime enable %s" % self.service_name)
File "/Users/HGI/Program/env3/lib/python3.8/site-packages/airtest/core/android/adb.py", line 361, in shell
out = self.raw_shell(cmd)
File "/Users/HGI/Program/env3/lib/python3.8/site-packages/airtest/core/android/adb.py", line 319, in raw_shell
out = self.cmd(cmds, ensure_unicode=False)
File "/Users/HGI/Program/env3/lib/python3.8/site-packages/airtest/core/android/adb.py", line 177, in cmd
if re.search(DeviceConnectionError.DEVICE_CONNECTION_ERROR, stderr):
File "/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/re.py", line 201, in search
return _compile(pattern, flags).search(string)
TypeError: cannot use a string pattern on a bytes-like object

```

**复现步骤**
我的代码
```
from airtest.core.api import auto_setup
auto_setup(__file__)

from poco.drivers.android.uiautomation import AndroidUiautomationPoco
poco = AndroidUiautomationPoco(screenshot_each_action=False)
```

**python 版本:** `python3.8`

**pocoui 版本:** `1.0.80`

**设备:**
- 型号: google pixel one
- 系统: Android 9

**运行环境**
MacBook Air (13-inch, Early 2014)
处理器 1.4 GHz Intel Core i5
内存 4 GB 1600 MHz DDR3
macOS 10.14.6
PyCharm 2020.3 (Community Edition)