Stuck processor on App Controller after deleting application with incomplete operation

[alexmt]

Describe the bug
Controller operation processor might stuck if an application in incomplete operation got deleted.

To Reproduce
Steps are not 100% reliable and might require several attempts:

1. Create an application and start syncing
2. Before sync is completed delete application using kubectl
3. Controller keeps trying to update deleted application forever

Expected behavior
The controller should stop updating the app if it is deleted.

Screenshots
If applicable, add screenshots to help explain your problem.

Version: v1.0.1

Logs

15:17:32  controller | DEBU[0904] Start Update application operation state
15:17:32  controller | DEBU[0904] Failed to Update application operation state: applications.argoproj.io "argocd-e2e-blcoe" not found, retrying in 1s
15:17:33  controller | DEBU[0905] Start Update application operation state
15:17:33  controller | DEBU[0905] Failed to Update application operation state: applications.argoproj.io "argocd-e2e-blcoe" not found, retrying in 1s
15:17:34  controller | DEBU[0906] Start Update application operation state
15:17:34  controller | DEBU[0906] Failed to Update application operation state: applications.argoproj.io "argocd-e2e-blcoe" not found, retrying in 1s
15:17:35  controller | DEBU[0907] Start Update application operation state
15:17:35  controller | DEBU[0907] Failed to Update application operation state: applications.argoproj.io "argocd-e2e-blcoe" not found, retrying in 1s
15:17:36  controller | DEBU[0908] Start Update application operation state
15:17:36  controller | DEBU[0908] Failed to Update application operation state: applications.argoproj.io "argocd-e2e-blcoe" not found, retrying in 1s
15:17:37  controller | DEBU[0909] Start Update application operation state
15:17:37  controller | DEBU[0909] Failed to Update application operation state: applications.argoproj.io "argocd-e2e-blcoe" not found, retrying in 1s
15:17:38  controller | DEBU[0910] Start Update application operation state
15:17:38  controller | DEBU[0910] Failed to Update application operation state: applications.argoproj.io "argocd-e2e-blcoe" not found, retrying in 1s
15:17:39  controller | DEBU[0911] Start Update application operation state
15:17:39  controller | DEBU[0911] Failed to Update application operation state: applications.argoproj.io "argocd-e2e-blcoe" not found, retrying in 1s
15:17:40  controller | DEBU[0912] Start Update application operation state
15:17:40  controller | DEBU[0912] Failed to Update application operation state: applications.argoproj.io "argocd-e2e-blcoe" not found, retrying in 1s
15:17:41  controller | DEBU[0913] Start Update application operation state
15:17:41  controller | DEBU[0913] Failed to Update application operation state: applications.argoproj.io "argocd-e2e-blcoe" not found, retrying in 1s
15:17:42  controller | DEBU[0914] Start Update application operation state
15:17:42  controller | DEBU[0914] Failed to Update application operation state: applications.argoproj.io "argocd-e2e-blcoe" not found, retrying in 1s
15:17:43  controller | DEBU[0915] Start Update application operation state
15:17:43  controller | DEBU[0915] Failed to Update application operation state: applications.argoproj.io "argocd-e2e-blcoe" not found, retrying in 1s
15:17:44  controller | DEBU[0916] Start Update application operation state
15:17:44  controller | DEBU[0916] Failed to Update application operation state: applications.argoproj.io "argocd-e2e-blcoe" not found, retrying in 1s
15:17:45  controller | DEBU[0917] Start Update application operation state
15:17:45  controller | DEBU[0917] Failed to Update application operation state: applications.argoproj.io "argocd-e2e-blcoe" not found, retrying in 1s
15:17:46  controller | DEBU[0918] Start Update application operation state
15:17:46  controller | DEBU[0918] Failed to Update application operation state: applications.argoproj.io "argocd-e2e-blcoe" not found, retrying in 1s
15:17:47  controller | DEBU[0919] Start Update application operation state
15:17:47  controller | DEBU[0919] Failed to Update application operation state: applications.argoproj.io "argocd-e2e-blcoe" not found, retrying in 1s
15:17:48  controller | DEBU[0920] Start Update application operation state
15:17:48  controller | DEBU[0920] Failed to Update application operation state: applications.argoproj.io "argocd-e2e-blcoe" not found, retrying in 1s
15:17:49  controller | DEBU[0921] Start Update application operation state
15:17:49  controller | DEBU[0921] Failed to Update application operation state: applications.argoproj.io "argocd-e2e-blcoe" not found, retrying in 1s
15:17:50  controller | DEBU[0922] Start Update application operation state
15:17:50  controller | DEBU[0922] Failed to Update application operation state: applications.argoproj.io "argocd-e2e-blcoe" not found, retrying in 1s
15:17:51  controller | DEBU[0923] Start Update application operation state
15:17:51  controller | DEBU[0923] Failed to Update application operation state: applications.argoproj.io "argocd-e2e-blcoe" not found, retrying in 1s
15:17:52  controller | DEBU[0924] Start Update application operation state
15:17:52  controller | DEBU[0924] Failed to Update application operation state: applications.argoproj.io "argocd-e2e-blcoe" not found, retrying in 1s
15:17:53  controller | DEBU[0925] Start Update application operation state
15:17:53  controller | DEBU[0925] Failed to Update application operation state: applications.argoproj.io "argocd-e2e-blcoe" not found, retrying in 1s

[alexmt]

Fixed