feat(dapi): use broadcast_tx instead of deprecated broadcast_tx_sync

[markin-io]

Issue being fixed or feature implemented

Replaced broadcas_tx_sync Tednerdash call with broadcast_tx in DAPI.

Currently, broadcas_tx_sync is an alias to broadcas_tx call in Tenderdash.
@lklimek deprecates it.

What was done?

How Has This Been Tested?

Breaking Changes

Checklist:

• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have added or updated relevant unit/integration/functional/e2e tests
• I have added "!" to the title and described breaking changes in the corresponding section if my code contains any
• I have made corresponding changes to the documentation if needed

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