Crash on Logout: Fatal Error in `WPAccount+RestApi.swift` due to Nil optional

[pmusolino]

After:

1. Switching websites
2. Navigating to the "Me" menu
3. Pressing logout

I encountered the following crash.

WordPress/WPAccount+RestApi.swift:15: Fatal error: Unexpectedly found nil while implicitly unwrapping an Optional value

[dangermattic]

Thanks for reporting! 👍

[pmusolino]

Following the same steps, but using Network Link Conditioner, I encountered a different type of crash.

WordPress/DomainsService.swift:165: Fatal error: Tried to obtain a Blog for a non-existing site (ID: 171745248)

[pmusolino]

Again, following the steps with Network Link Contioner enabled, created this other crash in core data:

*** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'Invalid parameter not satisfying: account.managedObjectContext == context'
*** First throw call stack:
(
	0   CoreFoundation                      0x00000001804c88c0 __exceptionPreprocess + 172
	1   libobjc.A.dylib                     0x00000001800937cc objc_exception_throw + 72
	2   Foundation                          0x0000000180e69804 _userInfoForFileAndLine + 0
	3   Jetpack.debug.dylib                 0x00000001136b7524 -[AccountService updateDefaultBlogIfNeeded:inContext:] + 204
	4   Jetpack.debug.dylib                 0x00000001136b73f4 __54-[AccountService updateAccountWithID:withUserDetails:]_block_invoke.78 + 124
	5   Jetpack.debug.dylib                 0x000000011457ead8 $sSo22NSManagedObjectContextCIeyBy_ABIegg_TR + 32
	6   Jetpack.debug.dylib                 0x000000011457e468 $s9WordPress14ContextManagerC14performAndSaveyyySo015NSManagedObjectC0CcFyyXEfU_ + 92
	7   Jetpack.debug.dylib                 0x000000011375dbf0 $sIg_Ieg_TR + 20
	8   Jetpack.debug.dylib                 0x000000011375dc14 $sIeg_IyB_TR + 24
	9   CoreData                            0x0000000186e9b0c4 developerSubmittedBlockToNSManagedObjectContextPerform + 224
	10  libdispatch.dylib                   0x0000000104699798 _dispatch_client_callout + 12
	11  libdispatch.dylib                   0x0000000104690374 _dispatch_lane_barrier_sync_invoke_and_complete + 144
	12  CoreData                            0x0000000186e9af8c -[NSManagedObjectContext performBlockAndWait:] + 304
	13  Jetpack.debug.dylib                 0x000000011457e3a8 $s9WordPress14ContextManagerC14performAndSaveyyySo015NSManagedObjectC0CcF + 376
	14  Jetpack.debug.dylib                 0x000000011457ea90 $s9WordPress14ContextManagerC14performAndSaveyyySo015NSManagedObjectC0CcFTo + 112
	15  Jetpack.debug.dylib                 0x00000001136b7088 -[AccountService updateAccountWithID:withUserDetails:] + 552
	16  Jetpack.debug.dylib                 0x00000001136b6aa8 __62-[AccountService updateUserDetailsForAccount:success:failure:]_block_invoke + 108
	17  WordPressKit                        0x0000000104b97580 __65-[AccountServiceRemoteREST getAccountDetailsWithSuccess:failure:]_block_invoke + 64
	18  WordPressKit                        0x0000000104cf1b70 $syXlSo17NSHTTPURLResponseCSgIeyByy_ypACIegng_TR + 68
	19  WordPressKit                        0x0000000104cf19e0 $sypSo17NSHTTPURLResponseCSgIegng_yXlACIeggg_TR + 68
	20  WordPressKit                        0x0000000104ced324 $s12WordPressKit0aB10ComRestApiC13multipartPOST_10parameters9fileParts15requestEnqueued7success7failureSo10NSProgressCSgSS_SDySSyXlGSgSaySo8FilePartCGySo8NSNumberCcSgyyXl_So17NSHTTPURLResponseCSg	21  WordPressKit                        0x0000000104bc1fc9 $sSo23ReaderPostServiceRemoteC12WordPressKitE5fetch33_2A107F88AE983644AA3B9A9C6EC5A248LL_7success7failureySS_ySayAC0dA4CardVG_SSSgtcys5Error_pctFyyYacfU_TATQ0_ + 1
	22  WordPressKit                        0x0000000104bb10f1 $sxIeAgHr_xs5Error_pIegHrzo_s8SendableRzs5NeverORs_r0_lTRyt_Tg5TQ0_ + 1
	23  WordPressKit                        0x0000000104bb1279 $sxIeAgHr_xs5Error_pIegHrzo_s8SendableRzs5NeverORs_r0_lTRyt_Tg5TATQ0_ + 1
	24  libswift_Concurrency.dylib          0x000000024a3159c9 _ZL23completeTaskWithClosurePN5swift12AsyncContextEPNS_10SwiftErrorE + 1
)
libc++abi: terminating due to uncaught exception of type NSException