[sonic-utilities][202012] submodule update (#7981)

Update submodule for sonic-utilities to include the following PRs:

Make the soft-reboot available in the SONiC image on master (#1681)
[config]: Update environment file during config reload (#1673)
Enable pr checker form 202012 (#1649)
[config] support for configuring muxcable to manual mode of operation (#1642)
[config] Fix config int add incorrect ip (#1414)

Signed-off-by: Dror Prital <drorp@nvidia.com>