Postgres database: support TLS/SSL connection settings

[1u0]

Arroyo currently doesn't support TLS connection (settings) to a Postgres used as database backend.
The Postgres connection settings are limited to:

arroyo/crates/arroyo/src/main.rs

Lines 193 to 198 in 613d194

	let mut cfg = deadpool_postgres::Config::new();
	cfg.dbname = Some(config.database_name.clone());
	cfg.host = Some(config.host.clone());
	cfg.port = Some(config.port);
	cfg.user = Some(config.user.clone());
	cfg.password = Some((*config.password).clone());

arroyo/crates/arroyo/src/main.rs

Lines 331 to 337 in 613d194

	match tokio_postgres::config::Config::new()
	.host(&config.host)
	.port(config.port)
	.user(&config.user)
	.password(&*config.password)
	.dbname(&config.database_name)
	.connect(NoTls)

In some Postgres setups, it might be a requirement to use or the DB forces to use TLS/SSL only connections.
Would be nice to at least support configuring Postgres SSL mode setting.

Note: maybe it would be more convenient to allow configuring Postgres connection via URL format (postgres://...), with possibility to override some of the parameters separately (mainly to support setting password via environment variable).