Add tests for LibSQL

[haaawk]

to run them execute:

export SQLX_LIBSQL_DSN="wss://<db url>?jwt=<access token>" export SQLX_SQLITE_DSN=skip export SQLX_POSTGRES_DSN=skip export SQLX_MYSQL_DSN=skip

go test -v -count=1 ./...

[haaawk]

The purpose of this PR is mostly to start a discussion around whether SQLX would be willing to accept contribution of LibSQL related tests. LibSQL is an open contribution fork of SQLite that also supports server deployments and replication. It follows SQLite SQL dialect so all the tests are reusing SQLite SQLs.

[dlsniper]

Hello, @ardan-bkennedy, and I recently stepped in to help maintain this project. We are sorting the opened issues and pull requests and would like to know if you still NEED this merged. Thank you for your contribution.

[haaawk]

Hi @dlsniper, yes. I will update the PR. Thank you.