[fix](nereids) convert stringLikeLiteral to double should use byte length (#43776) branch-2.0

[englefly]

What problem does this PR solve?

pick #43776

The optimizer maps different data types to Double, allowing for a unified comparison of literals.
StringLikeLiteral is regarded as a long int, and map the long int to double.
To extract the first N bytes from a string, you should use String.getBytes().length instead of String.length().

Issue Number: close #xxx

Related PR: #xxx

Problem Summary:

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• Behavior changed:

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[englefly]

run buildall