feat(expr): support a single ascii char as escape in LIKE

[TennyZhuang]

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What's changed and what's your intention?

Resolve #15701

There are some improvements should be done later, will record in another issue.

• Support '_' as escape char in LIKE
• Support '' as escape char in LIKE
• Support UTF-8 characters as escape chars in LIKE

Checklist

• I have written necessary rustdoc comments
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Release note

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[yuhao-su]

LGTM

[BugenZhao]

🆒