Document update conflict reported in feedback docs

[binokaryg]

Describe the bug
In the month of May 2021, the feedback documents for brac-ug (3.9.2) had this error recorded 38 times from 31 users:

Possibly unhandled rejection: {"status":409,"name":"conflict","message":"Document update conflict","error":true}

Most of these are from the tasks page, and others from the contacts and targets page:

Location based on URL	Count (May 2021)
Tasks page	26
Contacts page	6
Targets page	2
Specific contact	1
Family survey form from contact	1
Family survey task	1
About page	1

Logs

Here is the top-level argument for each of the 38 incidents (brac-ug, May 2021):

Level	Arguments	Count
warn	db.type() is deprecated and will be removed in a future version of PouchDB	18
error	Error updating _local/rulesStateStore: {\"status\":409,\"name\":\"conflict\",\"message\":\"Document update conflict\"}	7
warn	MaxListenersExceededWarning","2":"Possible EventEmitter memory leak detected. 11 \"destroyed\" listeners added. Use emitter.setMaxListeners() to increase limit.	4
warn	No active pages found. Make sure your form has at least one relevant input.	4
info	The above 404 is totally normal. PouchDB is just checking if a remote checkpoint exists.	4
log	Data node: /*/meta/deprecatedID with null-based index: undefined not found. Ignored.	1

Environment

• Instance: brac-ug.app.medicmobile.org
• Version: 3.9.2

Additional context
This error is being recorded every month since we started collecting the feedback docs in August 2020, the highest being 80 times in September 2020, followed by 75 times in March 2021 for brac-ug.

Similar error is also recorded for pih-malawi every month, although less frequent (1-14 times a month).

[kennsippell]

roughly 163 docs matching this pattern this month for PIH production data

[dianabarsan]

I'm hitting the Error updating _local/rulesStateStore: {\"status\":409,\"name\":\"conflict\",\"message\":\"Document update conflict\"} error consistently in an e2e test once I started recording feedback docs every time console.error is called.