revert changes to empty string as present for lower_bound, upper_bound,or index_value

[huangminghuang]

Change Description

The PR

• reverts the change in PR 9988 which treat empty string as present for lower_bound, upper_bound and index_value in kv table query.
• removes the bytes default for get_kv_table_rows_params.encode_type

Change Type

Select ONE:

• Documentation

• Stability bug fix

• Other

• Other - special case

Testing Changes

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• New Tests

• Existing Tests

• Test Framework

• CI System

• Other

Consensus Changes

• Consensus Changes

API Changes

• API Changes

The encode_type field of get_kv_table_rows is not defaulted to "bytes" any longer and is defaulted based off of the abi type for the "index_param". It is defaulted to "name" for a name type, "string" for string type, and "dec" for integer types.

Documentation Additions

• Documentation Additions