[202012] update sonic-utilities submodule (#9195)

Submodule update for sonic-utilties

```
48035d7 [202012] [techsupport] Techsupport Error Reporting pending fixes (sonic-net#1854)
8b2ec09 Fix log_ssd_health hang issue (sonic-net#1904)
ac9c425 Fix the option missing in kernel config issue (sonic-net#1888)
5cc9417 disk_check: Script updated to run good in 201811 & 201911 (sonic-net#1747)
```