FINERACT-2165: Migrate TaxComponentHelper and TaxGroupHelper to fineract-client-feign

[elnafateh]

Description

Part of FINERACT-2165 — system-wide migration of integration tests from RestAssured to fineract-client-feign.

This PR completes the migration of TaxComponentHelper and TaxGroupHelper, and updates the 3 test files that called their now-removed deprecated methods.

Checklist

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[elnafateh]

kindly rerun failed test, it's flaky

[adamsaghy]

LGTM