Adding tests structure with some basic tests

[ineersa]

Added orchestra/testbench to test package.
Added composer commands:

"post-autoload-dump": [
            "@clear",
            "@prepare"
        ],
        "clear": "@php vendor/bin/testbench package:purge-skeleton --ansi",
        "prepare": "@php vendor/bin/testbench package:discover --ansi",
        "build": "@php vendor/bin/testbench workbench:build --ansi",
        "serve": [
            "Composer\\Config::disableProcessTimeout",
            "@build",
            "@php vendor/bin/testbench serve"
        ],
        "lint": [
            "@php vendor/bin/pint",
            "@php vendor/bin/phpstan analyse"
        ],
        "phpstan-baseline": [
            "@php vendor/bin/phpstan -b"
        ],
        "test": [
            "@php vendor/bin/phpunit"
        ],
        "test-feature": [
            "@php vendor/bin/phpunit --testsuite=Feature"
        ],
        "test-unit": [
            "@php vendor/bin/phpunit --testsuite=Unit"
        ]

Added some basic tests:

• \Turso\Driver\Laravel\Tests\Feature\ConnectionsSetupTest - tests how connection configuration setup is working
• \Turso\Driver\Laravel\Tests\Feature\CreateRecordsTest - tests new record creation

To run single test you can use ./vendor/bin/phpunit --filter=CreateRecordsTest::testCreateViaEloquent

I've decided not to put errors into phpstan baseline, si8nce some of them should be fixed.