Clarify unsafeTeleportDestination message

[Haarolean]

Information

This PR fixes #5088.

Details

Proposed fix:

1. I've analyzed the usage of unsafeTeleportDestination message in all the places, two of them seem to use the message correctly (com/earth2me/essentials/Teleport.java:156 and com/earth2me/essentials/AsyncTeleport.java:207)
2. The problematic one in com/earth2me/essentials/commands/Commandsethome.java:59 needed some clarification as the message could be triggered via isForceDisableTeleportSafety being disabled, for example. I've altered the wording of the message to prevent adding additional messages or passing config param states into i18n.
3. Refactored the if clause in Commandsethome.java to make it more readable.

Environments tested:

OS:

Java version:

• [ ] Most recent Paper version (1.XX.Y, git-Paper-BUILD)
• [ ] CraftBukkit/Spigot/Paper 1.12.2
• [ ] CraftBukkit 1.8.8

Demonstration: