Add handling for txpool_newTransaction event

[nagdahimanshu]

What was the problem?

This PR resolves #2006

How was it solved?

• Add handling for txpool_newTransaction event
• Emit event transaction.new in case of txpool_newTransaction event as well
• Update pending transaction list when txpool_newTransaction event is received

How was it tested?

Local + Server

[codecov]

Codecov Report

Attention: 2 lines in your changes are missing coverage. Please review.

Comparison is base (a4248c1) 68.07% compared to head (aaba729) 68.07%.

❗ Current head aaba729 differs from pull request most recent head 958d3c1. Consider uploading reports for the commit 958d3c1 to get more accurate results

Additional details and impacted files

@@               Coverage Diff               @@
##           development    #2009      +/-   ##
===============================================
- Coverage        68.07%   68.07%   -0.01%     
===============================================
  Files              299      299              
  Lines             5338     5344       +6     
  Branches           977      977              
===============================================
+ Hits              3634     3638       +4     
- Misses            1704     1706       +2     

Files	Coverage Δ
...chain-indexer/shared/dataService/business/index.js	100.00% <100.00%> (ø)
...ces/blockchain-indexer/shared/dataService/index.js	100.00% <ø> (ø)
...shared/dataService/business/pendingTransactions.js	91.20% <91.30%> (-1.74%)	⬇️