Jayj/old table timestamped

[jayjanssen]

• Extends the old table name to include the current timestamp, but only if --skip-drop-after-cutover is used.
  • This helps distinguish old table and prevent multiple old tables from being deleted
  • This has the potential of leaving more orphaned "old" tables in some tests since their names are now dynamic
• Check the table name length early in Preflight checks.
• Calculates the possible lengths on runtime based on the table suffix formats.

Fixes https://github.com/cashapp/spirit/issues/296

[morgo]

Change LGTM when you are ready to merge. I like the design.