feat: ignore varchar with length

[fuyufjh]

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What's changed and what's your intention?

Part of #17037.

Preview:

dev=> create table t1 (c1 varchar, c2 varchar(10));
NOTICE:  CHARACTER VARYING with length is not supported. The length is ignored.
CREATE_TABLE

dev=> create table t2 (c1 varchar, c2 varchar(10), c3 varchar(10000));
NOTICE:  CHARACTER VARYING with length is not supported. The length is ignored.
NOTICE:  CHARACTER VARYING with length is not supported. The length is ignored.
CREATE_TABLE

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[neverchanje]

Thanks. This LGTM, but it may still not be able to solve my intial problem.