Python WARNINGs for empty APPL_DB appear on syslog

[vaibhavhd]

Description
Multiple APPL_DB warnings keep appearing on syslog.

Nov 20 18:05:16.629193 str-7260cx3-acs-7 WARNING python: :- operator(): DB '{APPL_DB}' is empty!
Nov 20 18:05:18.115823 str-7260cx3-acs-7 WARNING python: :- operator(): DB '{APPL_DB}' is empty!
Nov 20 18:05:18.998459 str-7260cx3-acs-7 WARNING python: :- operator(): DB '{APPL_DB}' is empty!
Nov 20 18:05:21.116698 str-7260cx3-acs-7 INFO ntpd[2669]: kernel reports TIME_ERROR: 0x41: Clock Unsynchronized
Nov 20 18:05:21.117102 str-7260cx3-acs-7 NOTICE ntpd[2669]: frequency error 1026 PPM exceeds tolerance 500 PPM
Nov 20 18:05:26.719989 str-7260cx3-acs-7 WARNING python: :- operator(): DB '{APPL_DB}' is empty!
Nov 20 18:05:46.181149 str-7260cx3-acs-7 WARNING python: :- operator(): DB '{APPL_DB}' is empty!
Nov 20 18:05:47.782424 str-7260cx3-acs-7 WARNING python: :- operator(): DB '{APPL_DB}' is empty!
Nov 20 18:05:48.885872 str-7260cx3-acs-7 WARNING python: :- operator(): DB '{APPL_DB}' is empty!
Nov 20 18:05:53.570206 str-7260cx3-acs-7 WARNING python: :- operator(): DB '{APPL_DB}' is empty!
Nov 20 18:05:54.568577 str-7260cx3-acs-7 WARNING python: :- operator(): DB '{APPL_DB}' is empty!
Nov 20 18:07:10.994846 str-7260cx3-acs-7 WARNING python: :- operator(): DB '{APPL_DB}' is empty!
Nov 20 18:07:29.710888 str-7260cx3-acs-7 WARNING python: :- operator(): DB '{APPL_DB}' is empty!
Nov 20 18:07:30.575684 str-7260cx3-acs-7 WARNING python: :- operator(): DB '{APPL_DB}' is empty!
Nov 20 18:08:51.647147 str-7260cx3-acs-7 WARNING python: :- operator(): DB '{APPL_DB}' is empty!

Steps to reproduce the issue:

1. Install latest of master - I tried 498.
2. Check syslog.
3. The messages keep appearing in regular intervals.

Describe the results you received:

Warnings in syslog.

Describe the results you expected:

Additional information you deem important (e.g. issue happens only occasionally):

**Output of `show version`:**

root@str-7260cx3-acs-7:/var/log# show ver

SONiC Software Version: SONiC.master.498-5fbb6ee6
Distribution: Debian 10.6
Kernel: 4.19.0-9-2-amd64
Build commit: 5fbb6ee6
Build date: Fri Nov 20 14:36:29 UTC 2020
Built by: johnar@jenkins-worker-3

Platform: x86_64-arista_7260cx3_64

**Attach debug file `sudo generate_dump`:**

```
(paste your output here)
```