[action] [PR:16737] [Chassis] Add extra wait after port toggle so that the routes got programmed into hardware


Description of PR
Summary:
Fixes #30114164

Approach
What is the motivation for this PR?
Fixes #30114164, test_acl is flaky on chassis device.
We observe flakiness failure on chassis devices
Suspect it's because the route is not programmed into hardware
Add external sleep to make sure route is in hardware

How did you do it?
Add extra waiting time for chassis device port toggle tests.

How did you verify/test it?
Run on PR test, and physical test is running.

[202012][sonic-linkmgrd]Submodule update

8507629 Jing Zhang      Mon Apr 4 10:25:22 2022 -0700   Lower unsolicited MUX state change notification log level to WARNING sonic-net#57
17d217d Longxiang Lyu   Mon Mar 21 12:15:19 2022 +0800  Enhance clang format (sonic-net#46)
c72fa2a Jing Zhang      Fri Apr 1 12:23:29 2022 -0700   Disable the feature that decreases link probe interval for measuring switch overhead sonic-net#49 (sonic-net#54)
256b01b Jing Zhang      Thu Mar 31 16:20:00 2022 -0700  Update link prober metrics posting logics sonic-net#50 sonic-net#53
dfd48d0 Jing Zhang      Wed Mar 23 16:27:45 2022 -0700  Decrease link probing interval after switchover to better determine the overhead of a toggle sonic-net#43 (sonic-net#48)

sign-off: Jing Zhang zhangjing@microsoft.com

…cause file removal issue (sonic-host-services sonic-net#46) (sonic-net#14106)

Why I did it
Porting/cherry-pick PR sonic-net/sonic-host-services#46
"show reboot-cause history" shows empty history. When the previous-reboot-cause has a broken symlink, And rebooting the system will not be able to generate a new symlink of the new previous-reboot-cause.

admin@sonic:~$ show reboot-cause history 
Name    Cause    Time    User    Comment
------  -------  ------  ------  ---------
How I did it
Somehow, when the symlink file /host/reboot-cause/previous-reboot-cause is broken (which its destination files doesn't exist in this case), the current condition check "if os.path,exists(PREVIOUS_REBOOT_CAUSE_FILE)" will return False in determine-reboot-cause script. Hence, the current previous-reboot-cause is not been removed and the recreation of the new previous-reboot-cause failed. In case of previous-reboot-cause is a broken synlink file, add condition os.path.islink(PREVIOUS_REBOOT_CAUSE) to check and allow the remove operation happens.

How to verify it
Manually make the /host/reboot-cause/previous-reboot-cause to be a broken symlink file by removing its destination file
reboot the system. "show reboot-cause history" should show the correct info

Signed-off-by: mlok <marty.lok@nokia.com>

Signed-off-by: Andriy Moroz <c_andriym@mellanox.com>