Indexing issues against the testnet

[sameersubudhi]

What was the problem?

This PR resolves #1898

How was it solved?

• Update getTransactionExecutionStatus to check topics both with and without the transaction topic prefixes
• Remove betanet support from app-registry
• Add null check to standardizeCurrencyConversionRates to prevent from crashing

How was it tested?

• Ran the branch against the testnet
• Ran it against a devnet node and posted all kinds of transactions with yarn test:stress script

[codecov]

Codecov Report

Merging #1899 (f019cf3) into release/0.7.0 (8d4a2f8) will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@              Coverage Diff               @@
##           release/0.7.0    #1899   +/-   ##
==============================================
  Coverage          66.62%   66.63%           
==============================================
  Files                298      298           
  Lines               5229     5230    +1     
  Branches             941      942    +1     
==============================================
+ Hits                3484     3485    +1     
  Misses              1745     1745           

Files	Coverage Δ
services/blockchain-app-registry/config.js	100.00% <100.00%> (ø)
...es/blockchain-indexer/shared/utils/transactions.js	100.00% <100.00%> (ø)