Machines in waiting state often reboot without telling it before

[Gerrit91]

Happens all the time still. Issue was already pointed out in #324. See this event log for instance (I annotated a bit with comments):

TIME                            EVENT            MESSAGE                                                                                                     
Mon, 11 Sep 2023 00:32:16 UTC   Waiting          waiting for allocation                                                                                        
Mon, 11 Sep 2023 00:31:58 UTC   Registering      start registering                                                                                             
Mon, 11 Sep 2023 00:31:58 UTC   Preparing        starting metal-hammer version:"v0.11.5 (7dda3a82), tags/v0.11.5-0-g7dda3a8, 2023-07-03T07:07:35Z, go1.20.5"   
Mon, 11 Sep 2023 00:30:13 UTC   PXE Booting      machine sent extended dhcp request                                                                            
Mon, 11 Sep 2023 00:28:57 UTC   Planned Reboot  ---> GOOD! autoreboot after 24h                                                                                          
Sat, 09 Sep 2023 20:56:19 UTC   Waiting          waiting for allocation                                                                                        
Sat, 09 Sep 2023 20:55:56 UTC   Registering      start registering                                                                                             
Sat, 09 Sep 2023 20:55:55 UTC   Preparing        starting metal-hammer version:"v0.11.5 (7dda3a82), tags/v0.11.5-0-g7dda3a8, 2023-07-03T07:07:35Z, go1.20.5"   
Sat, 09 Sep 2023 20:54:11 UTC   PXE Booting    ---> BAD!  [unexpectedly received in state waiting]: machine sent extended dhcp request                                  
Fri, 08 Sep 2023 15:58:12 UTC   Waiting          waiting for allocation                                                                                        
Fri, 08 Sep 2023 15:57:55 UTC   Registering      start registering                                                                                             
Fri, 08 Sep 2023 15:57:55 UTC   Preparing        starting metal-hammer version:"v0.11.5 (7dda3a82), tags/v0.11.5-0-g7dda3a8, 2023-07-03T07:07:35Z, go1.20.5"   
Fri, 08 Sep 2023 15:56:15 UTC   PXE Booting    ---> BAD!  [unexpectedly received in state waiting]: machine sent extended dhcp request                                  
Thu, 07 Sep 2023 12:35:18 UTC   Waiting          waiting for allocation                                                                                        
Thu, 07 Sep 2023 12:35:01 UTC   Registering      start registering                                                                                             
Thu, 07 Sep 2023 12:35:00 UTC   Preparing        starting metal-hammer version:"v0.11.5 (7dda3a82), tags/v0.11.5-0-g7dda3a8, 2023-07-03T07:07:35Z, go1.20.5"   
Thu, 07 Sep 2023 12:33:15 UTC   PXE Booting      machine sent extended dhcp request                                                                            
Thu, 07 Sep 2023 12:32:00 UTC   Planned Reboot  ---> GOOD! autoreboot after 24h                                                                                          
Wed, 06 Sep 2023 02:55:16 UTC   Waiting          waiting for allocation                                                                                        
Wed, 06 Sep 2023 02:54:59 UTC   Registering      start registering 

This is messing up the machine issues output.

[Gerrit91]

It can also happen that an alive events gets sent after planned reboot was announced (even if likeliness seems to be low):

TIME                            EVENT   MESSAGE                                                                                                                  
Fri, 03 Nov 2023 08:42:14 UTC   Alive   [unexpectedly received in state planned reboot]: still alive at: 2023-11-03 08:42:14.273220579 +0000 UTC m=+57360.738...