3.4.0-dev-0.20240912.4ef2a82e6

Changelog

• 4ef2a82 feat(cluster_test): test empty --host in SM DB
• f0faa48 fix(scyllaclient): don't panic on empty host in client
• ed87d32 fix(cluster): don't assume that --host is set
• aa77cb7 feat(cluster_test): test failed connectivity check on put cluster
• 37f6bc3 fix(cluster): don't insert known hosts before validation finishes