[nit] Migrate to docker compose v2

[stefafafan]

ref. https://docs.docker.com/compose/migrate/

When running the tests locally, I get messages like this.

$ make test
WARNING: Compose V1 is no longer supported and will be removed from Docker Desktop in an upcoming release. See https://docs.docker.com/go/compose-v1-eol/
mysql: [Warning] Using a password on the command line interface can be insecure.
WARNING: Compose V1 is no longer supported and will be removed from Docker Desktop in an upcoming release. See https://docs.docker.com/go/compose-v1-eol/
mysql: [Warning] Using a password on the command line interface can be insecure.
WARNING: Compose V1 is no longer supported and will be removed from Docker Desktop in an upcoming release. See https://docs.docker.com/go/compose-v1-eol/
mysql: [Warning] Using a password on the command line interface can be insecure.
WARNING: Compose V1 is no longer supported and will be removed from Docker Desktop in an upcoming release. See https://docs.docker.com/go/compose-v1-eol/
...

This is annoying, so I replaced docker-compose with docker compose. Now it is a lot simpler. This docker-compose file is only used for testing purposes so should not have any affect to users using go-txdb.

$ make test
mysql: [Warning] Using a password on the command line interface can be insecure.
mysql: [Warning] Using a password on the command line interface can be insecure.
mysql: [Warning] Using a password on the command line interface can be insecure.
mysql: [Warning] Using a password on the command line interface can be insecure.
DROP DATABASE
CREATE DATABASE
CREATE TABLE
INSERT 0 3
Opening db...
Opening db...
[nit] migrate to docker compose v2
PASS
ok  	github.com/DATA-DOG/go-txdb	0.439s