Support Values Query at ASTBuilder

[devgony]

Goal

Currently, ASTBuilder does not support Values Query yet.
This PR will support Values Query at ASTBuilder

let actual = values(vec!["1, 'a'", "2, 'b'"])
    .order_by(vec!["column1 desc"])
    .build();
let expected = "VALUES(1, 'a'), (2, 'b') ORDER BY column1 desc";

Todo

• implement entrypoint values()
• implement build
• look for the way to unify fn build with previous codes
• implement values.{order_by, limit, offset}

Next

• Support column alias for SELECT Query like SELECT * FROM Table AS T (C1, C2..) in core
• Support column alias for alias_as in AstBuilder

[coveralls]

Pull Request Test Coverage Report for Build 4150997881

• 219 of 224 (97.77%) changed or added relevant lines in 16 files are covered.
• 6 unchanged lines in 1 file lost coverage.
• Overall coverage decreased (-0.03%) to 98.613%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
test-suite/src/ast_builder/values.rs	59	64	92.19%

Files with Coverage Reduction	New Missed Lines	%
core/src/executor/alter/table.rs	6	94.92%

Totals
Change from base Build 4149756888:	-0.03%
Covered Lines:	38531
Relevant Lines:	39073

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💛 - Coveralls

[panarch]

Awesome!! All looks great 👍
Thanks a lot!