Fix SQLite migrations table insert statements

[bstanley-pec]

Description

While testing php artisan migrate:dump with SQLite I discovered an error with the output where both of the first two insert statements had an id of 1, which caused the php artisan migrate:load command to fail. I traced to error to a hard-coded array_slice() call where potentially the current version of SQLite compared to an older version of SQLite produces slightly different output. Making the values of $insert_rows dynamic fixes this issue with the current SQLite version and should also work with older versions as well.

Tests

I added a second migration to specifically highlight this issue and updated all of the dump tests to check that it works correctly with all supported database drivers.

Call outs

I added the ext-mbstring extension to the composer.json file due to various mb_* functions existing in the code base.