This PR adds test coverage for transaction tax report

Basic changes:

• Increases request timeout for dev mode
• Expands mocked trade data
• Fixes getTrades test case to consider new mock data
• Adds test cases for getTransactionTaxReport method
• Adds test case for getTransactionTaxReportFile method
• Reverses pub-trades array for trx tax report for test env as mocked test server returns data in desc order
• Add test coverage for trx tax report interruption

Depends on this PR:

• Increases math precision of the trx tax report using bignumber.js #386