[SYSTEMDS-3960] Fix federated worker readiness probe on delayed connections

[gaturchenko]

With any delay on the worker's interface, currently every federated test fails before it starts, while the worker is listening the whole time. FederatedWorkerUtils.tryConnect allocated 25ms per connect attempt, but a TCP handshake needs two traversals of the link which are ~100ms under the delay above. Every attempt expired with a SocketTimeoutException, which is an IOException and therefore indistinguishable from a closed port, so the probe never succeeded.

The following changes were implemented:

• Per-attempt connect budget increased from 25ms to 2s. A closed port is refused by the kernel immediately, so it only applies once a handshake is in progress. Additionally, 2s covers one lost SYN, retransmitted after ~1s
• Each attempt is capped by the time left until the overall deadline (attemptTimeout), so a slow connect cannot exceed it. The returned value of 0 implies the attempt was never made
• The waitForWorkers now rechecks the deadline per port, which can now cost up to 2s each
• Six new tests are added verifying the change