schemadiff: TableCharsetCollateStrategy hint

[shlomi-noach]

Description

schemadiff: adding a new hint, named TableCharsetCollateStrategy, which controls how schemadiff treats diffs in a table's CHARSET and COLLATE option values:

• TableCharsetCollateStrict - default, if charsets or collations are different, that's a diff.
• TableCharsetCollateIgnoreEmpty - if one of the tables has no value for CHARSET or COLLATE, ignore the diff (works whether the source table or target table have empty values)
• TableCharsetCollateIgnoreAlways - never generate a table charset/collate diff

Related Issue(s)

• schemadiff: tracking issue #10203

Checklist

• "Backport to:" labels have been added if this change should be back-ported
• Tests were added or are not required
• Documentation was added or is not required

Deployment Notes

[vitess-bot]

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[rohit-nayak-ps]

lgtm