Set SSH_AUTHORIZED_KEYS_BACKUP to false (#25412)

This prevents the disk from overflowing with auth keys file

Fixes #17117

## ⚠️ BREAKING

This changes the default option for creating a backup of the authorized
key file when an update is made to default to false.

modules/setting/ssh.go

@@ -173,7 +173,7 @@ func loadSSHFrom(rootCfg ConfigProvider) {
 		}
 	}
 
-	SSH.AuthorizedKeysBackup = sec.Key("SSH_AUTHORIZED_KEYS_BACKUP").MustBool(true)
+	SSH.AuthorizedKeysBackup = sec.Key("SSH_AUTHORIZED_KEYS_BACKUP").MustBool(false)
 	SSH.CreateAuthorizedKeysFile = sec.Key("SSH_CREATE_AUTHORIZED_KEYS_FILE").MustBool(true)
 
 	SSH.AuthorizedPrincipalsBackup = false