Fix AS query clause should be after the create table options

[git-hulk]

According to MySQL[1] and PostgreSQL[2] create table syntax, the AS query should be sit after the table options. But it is parsed before table options include CHARSET and COLLATE, as well as ON COMMIT clause. This PR resolves this issue by moving the position of AS query, and the issue #1274 will be aslo resolved after this PR.

MySQL:

CREATE [TEMPORARY] TABLE [IF NOT EXISTS] tbl_name
    [(create_definition,...)]
    [table_options]
    [partition_options]
    [IGNORE | REPLACE]
    [AS] query_expression

PostgreSQL:

CREATE [ [ GLOBAL | LOCAL ] { TEMPORARY | TEMP } | UNLOGGED ] TABLE [ IF NOT EXISTS ] table_name
    [ (column_name [, ...] ) ]
    [ USING method ]
    [ WITH ( storage_parameter [= value] [, ... ] ) | WITHOUT OIDS ]
    [ ON COMMIT { PRESERVE ROWS | DELETE ROWS | DROP } ]
    [ TABLESPACE tablespace_name ]
    AS query
    [ WITH [ NO ] DATA ]

[1] https://dev.mysql.com/doc/refman/8.0/en/create-table.html
[2] https://www.postgresql.org/docs/current/sql-createtableas.html

[coveralls]

Pull Request Test Coverage Report for Build 9927891212

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

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Details

• 32 of 32 (100.0%) changed or added relevant lines in 4 files are covered.
• 227 unchanged lines in 2 files lost coverage.
• Overall coverage increased (+0.005%) to 89.194%

---

Files with Coverage Reduction	New Missed Lines	%
tests/sqlparser_postgres.rs	21	87.95%
src/parser/mod.rs	206	93.29%

Totals
Change from base Build 9864598743:	0.005%
Covered Lines:	26858
Relevant Lines:	30112

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💛 - Coveralls

[alamb]

Makes sense to me -- thank you @git-hulk

cc @iffyio

[iffyio]

LGTM!

[alamb]

Looks good to me -- thank you @git-hulk and @iffyio