Add support Firebird 4.0+ datatypes

### Description

Currently the PDO Firebird driver does not support the data types introduced in Firebird 4.0:

- INT128
- NUMERIC(38, x) and DECIMAL(38, x)
- DECFLOAT(16) and DECFLOAT(34)
- TIMESTAMP WITH TIME ZONE and TIME WITH TIME ZONE

Since PHP still does not have native types that directly correspond to Firebird data types, it is proposed to map these data types to strings.