Lift up dialect specific methods in the CreateTableBuilder

[lorefnon]

Ref:

• table charset and collate doesnt exist #3478 (comment)
• table charset and collate doesnt exist #3478 (comment)

[kibertoad]

@lorefnon

 2) Integration Tests

       oracle | oracledb

         Joins

           accepts a callback as the second argument for advanced joins:

     select * from "accounts" left join "test_table_two" on "accounts"."id" = "test_table_two"."account_id" or "accounts"."email" = "test_table_two"."details" order by "accounts"."id" asc - ORA-00932: inconsistent datatypes: expected - got CLOB

  Error: ORA-00932: inconsistent datatypes: expected - got CLOB

      at Client_Oracledb._query (lib/dialects/oracledb/index.js:246:19)

      at Client_Oracledb.query (lib/client.js:165:17)

      at Runner.query (lib/runner.js:135:36)

      at /home/travis/build/knex/knex/lib/runner.js:39:23

  From previous event:

      at Runner.run (lib/runner.js:25:16)

      at Builder.Target.then (lib/interface.js:14:43)

I think this is a new failure. Can you check it out?

[lorefnon]

@kibertoad yeah, this broke due to an accidental change. Fixed now.