fix: handle etherscan rate limit errors

[matthewwalsh0]

Description

The mobile client uses the core TransactionController which supports the use of an API key when querying Etherscan for incoming or updated transactions.

The extension, using its TransactionController, only queries Etherscan for normal transactions using a single callout.

The mobile client, using the core TransactionController, queries Etherscan for both normal transactions and token transfer transactions related to an account. This requires 2 callouts and therefore consistently results in a rate limit error on one of the callouts if no API key is provided.

Previously, if either request failed due to a rate limit error, the update would be skipped, and no transactions would be added. This PR instead processes whatever transactions are found, regardless of which specific callout returned a rate limit error.

Since both callouts are performed simultaneously, it is currently random chance which callout results in the rate limit error, meaning both normal and token transfer transactions are still supported, but either could experience sporadic delays.

Additional changes include:

• Add back the background timer to ensure incoming transactions continue to be polled, even when the app is in background mode.
• Disable the startBlock argument in Etherscan requests to match the previous behaviour where a bug meant this was never being utilised.

Recordings

Transaction History After Import

import_history.mov

New Incoming Transaction & Notification

new_incoming.mov

Issue

Fixes #1249, #1250, #1251

Checklist

• There is a related GitHub issue
• Tests are included if applicable
• Any added code is fully documented

[github-actions]

CLA Signature Action: All authors have signed the CLA. You may need to manually re-run the blocking PR check if it doesn't pass in a few minutes.

[codecov-commenter]

Codecov Report

Patch coverage has no change and project coverage change: -0.01% ⚠️

Comparison is base (57dbc0e) 33.15% compared to head (100f485) 33.15%.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #7209      +/-   ##
==========================================
- Coverage   33.15%   33.15%   -0.01%     
==========================================
  Files        1005     1005              
  Lines       32656    32659       +3     
  Branches     8398     8398              
==========================================
  Hits        10827    10827              
- Misses      21829    21832       +3     

Files Changed	Coverage Δ
app/components/Nav/Main/index.js	6.20% <0.00%> (-0.14%)	⬇️
app/core/AppConstants.ts	85.71% <ø> (ø)

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[sonarcloud]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

0.0% Coverage
0.0% Duplication

[sleepytanya]

All incoming transaction notifications work as expected, push notification are also seen when the app is on the background.
iOS incoming transactions notifications (1- normal send / 2 - token transfer):

eth.mov

token.mov

iOS incoming transactions notifications in the background mode (1 - normal send / 2 - token transfer):

bckgr_send.mov

https://github.com/MetaMask/metamask-mobile/assets/104780023/240f14e9-b9ab-4bdb-96ae-aa3d04734283
Transaction history after import (iOS):

history_ios.mov

Android incoming ETH notification:

eth.mov

Android incoming token notification:

tst.mov

Android incoming ETH notification in background mode:

send_eth_bkgr.mov

Android incoming TST notification in background mode:

tst_bkgr.mov

Screen.Recording.2023-09-14.at.11.10.40.AM.mov

Transaction history after import on Android:

[sleepytanya]

LGTM

[sethkfman]

LGTM