regex warnings in MsftLinuxPatchCore.py?

从 MsftLinuxPatchCore.py 的第 7451、7468 和 7476 行开始，然后在 Ubuntu 24.04 Azure VM 上重现该问题，同时观察扩展日志。验证受影响的 regex 处理在 LinuxPatchExtension 启动期间不再发出无效转义序列警告。

Describe the bug
I see the following in my journalctl logs:

Aug 22 00:36:41 sr-monitor systemd[1]: Starting MsftLinuxPatchAutoAssess.service - Microsoft Azure Linux Patch Extension - Auto Assessment...
Aug 22 00:36:41 sr-monitor bash[143561]: /var/lib/waagent/Microsoft.CPlat.Core.LinuxPatchExtension-1.6.62/MsftLinuxPatchCore.py:7451: SyntaxWarning: invalid escape sequence '\_'
Aug 22 00:36:41 sr-monitor bash[143561]:   """ Fetches pid from the error message by searching for the text 'pid' and returns the process tree with all details.
Aug 22 00:36:41 sr-monitor bash[143561]: /var/lib/waagent/Microsoft.CPlat.Core.LinuxPatchExtension-1.6.62/MsftLinuxPatchCore.py:7468: SyntaxWarning: invalid escape sequence '\d'
Aug 22 00:36:41 sr-monitor bash[143561]:   regex = re.compile(' pid \d+')
Aug 22 00:36:41 sr-monitor bash[143561]: /var/lib/waagent/Microsoft.CPlat.Core.LinuxPatchExtension-1.6.62/MsftLinuxPatchCore.py:7476: SyntaxWarning: invalid escape sequence '\d'
Aug 22 00:36:41 sr-monitor bash[143561]:   regex = re.compile('\d+')

Is this a bug?

To Reproduce
Steps to reproduce the behavior:

1. Create Azure Ubuntu VM
2. Enable LinuxPatchExtension
3. Watch the logs

Expected behavior
No regex warnings

Screenshots
If applicable, add screenshots to help explain your problem.

Desktop (please complete the following information):

• OS: ubuntu
• Browser N/A
• Version 24_04-lts

Smartphone (please complete the following information):

• Device: [e.g. iPhone6]
• OS: [e.g. iOS8.1]
• Browser [e.g. stock browser, safari]
• Version [e.g. 22]

Additional context
Add any other context about the problem here.