Support "double precision" type in mysql

[nvoxland]

Description

Added handling for "double precision" which is a distinct type in mysql vs. just "double" https://dev.mysql.com/doc/refman/8.0/en/numeric-type-syntax.html

Fixes #2337

[XDelphiGrl]

With this fix, Liquibase generates correct SQL for MySQL columns configured in Liquibase changelogs with a DOUBLE PRECISION datatype. Note that MySQL treats DOUBLE PRECISION as a synonym for DOUBLE. This means that although Liquibase generates syntactically correct SQL to create a DOUBLE PRECISION column, if you view the table on the database OR run Liquibase generate-changelog, the datatype of the column will be DOUBLE. This is expected MySQL behavior.

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• Verify update-sql generates valid SQL for a column with DOUBLE PRECISION datatype. PASS

--  Changeset gcl1126.xml::1647019572747-2::erz (generated)
CREATE TABLE testdb1.double_precision_test (precision_column DOUBLE PRECISION(5, 2) NULL);

• Verify update with a DOUBLE PRECISION column is successful. PASS

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Test Environment
Liquibase Core: mysql-double-precision/1698/883393, Pro: master/672/56f847
MySQL 5.6, 5.7, 8.0
Functional Tests
Test Harness PR