[202012] Submodule Update on sonic-sairedis

[gechiang]

Why I did it

To pick up fixes from submodule sonic-sairedis which include the following fixes:

commit 1027eef3a331e84560827c7584ee8009baf434d5 (HEAD -> 202012, origin/202012)
Author: gechiang <62408185+gechiang@users.noreply.github.com>
Date:   Wed Dec 8 03:13:34 2021 -0800

    [202012] Prevent other notification event storms to keep enqueue unchecked and drained all memory that leads to crashing the switch router (#976)

commit 94455e50d3444dcd60093b7a39c7f427337a94d2
Author: VenkatCisco <77468614+VenkatCisco@users.noreply.github.com>
Date:   Tue Jun 15 03:23:20 2021 -0700

    Add cisco-8000 checks to syncd_init_common (#839)

commit 2df539483ed68519c3c9c6df958d3ed2f31dd629
Author: Kamil Cudnik <kcudnik@gmail.com>
Date:   Mon Dec 6 20:50:23 2021 +0100

    [lgtm] Add gmock libs to lgtm (#979)

Which release branch to backport (provide reason below if selected)

• 201811
• 201911
• 202006
• 202012
• 202106

Description for the changelog

[202012][Submodule Update sonic-sairedis] pick up 3 fixes

A picture of a cute animal (not mandatory but encouraged)