Pass all SQL test in spansql tests

[apstndb]

Result
https://github.com/apstndb/memefish-testsuite/blob/440786a9cead1c7d25a833c9c9de5868976e67e4/output/result.txt

• SYNONYMs in CREATE TABLE Support SYNONYMs in CREATE TABLE #125
• DROP VIEW statement Support DROP VIEW statement #126
• GRANT/REVOKE SELECT ON CHANGE STREAM Support GRANT/REVOKE SELECT ON CHANGE STREAM #127
• ALTER TABLE ALTER COLUMN DROP DEFAULT Incompatibility: ALTER COLUMN DROP DEFAULT #92
• ALTER TABLE ADD/DROP SYNONYM Support ALTER TABLE ADD/DROP SYNONYM #128
• ALTER TABLE RENAME TO, ADD SYNONYM Support ALTER TABLE RENAME TO, ADD SYNONYM #129
• ALTER STATISTICS Support ALTER STATISTICS statement #162
• RENAME TABLE statement Support RENAME TABLE statement #130
• ALTER DATABASE statement Support ALTER DATABASE statement #131
• UPDATE SET DEFAULT Support UPDATE SET DEFAULT #132
• SAFE_CAST(expr AS type) related Incompatibility: SAFE functions are not supported #94
• AGG_FUNC(IGNORE NULLS HAVING MAX) Support current spec of aggregate function calls #88
• JSON literals Support JSON literals #117

[apstndb]

Now we have passed all test in spansql's TestSQL()!
apstndb/memefish-testsuite@cfb6d62

It is a important milestone that memefish becomes the most feature complete parser for Cloud Spanner's GoogleSQL!