fix: do not save determination id until after successfully updating calendar

FreeAPS/Sources/Services/Calendar/CalendarManager.swift

@@ -216,7 +216,6 @@ final class BaseCalendarManager: CalendarManager, Injectable {
         if determinationId == previousDeterminationId {
             return
         }
-        previousDeterminationId = determinationId
 
         let glucoseIds = await fetchGlucose()
 
@@ -298,6 +297,9 @@ final class BaseCalendarManager: CalendarManager, Injectable {
 
             try eventStore.save(event, span: .thisEvent)
 
+            // Save the determination ID so we can avoid updating calendar if this determination comes back
+            previousDeterminationId = determinationId
+
         } catch {
             debugPrint(
                 "\(DebuggingIdentifiers.failed) \(#file) \(#function) Failed to create calendar event: \(error.localizedDescription)"