In ./src/SqliteSchema.php changed
protected function setRawCols(array &$cols, $schema, $table, $create)
to
protected function setRawCols(array &$cols, string $schema, string $table, string $create)
and
protected function addColFromRaw(array &$cols, array $val, $create)
to
protected function addColFromRaw(array &$cols, array $val, string $create)
Full Changelog: 3.1.0...3.1.1