add: manual cancellation result code

[alperozturk96]

Needed for nextcloud/android#15712

[nextcloud-android-bot]

master-IT test failed: https://www.kaminsky.me/nc-dev/android-library-integrationTests/4519-IT-master-10-12/debug/

[nextcloud-android-bot]

master-IT test failed: https://www.kaminsky.me/nc-dev/android-library-integrationTests/4520-IT-master-10-14/debug/

[github-actions]

SpotBugs

Category	Base	New
Bad practice	34	34
Correctness	34	34
Dodgy code	26	26
Internationalization	6	6
Malicious code vulnerability	49	49
Multithreaded correctness	11	11
Performance	8	8
Total	168	168

[alperozturk96]

/backport to stable-2.22

[alperozturk96]

@AndyScherzinger Could you check this? Thanks :)

[backportbot]

The backport to stable-2.22 failed. Please do this backport manually.

# Switch to the target branch and update it
git checkout stable-2.22
git pull origin stable-2.22

# Create the new backport branch
git checkout -b backport/1842/stable-2.22

# Cherry pick the change from the commit sha1 of the change against the default branch
# This might cause conflicts, resolve them
git cherry-pick cbf26be0 198270eb

# Push the cherry pick commit to the remote repository and open a pull request
git push origin backport/1842/stable-2.22

Error: Failed to clone repository: Failed to create working tree: Preparing worktree (new branch 'backport/1842/stable-2.22')
fatal: not a valid object name: 'origin/stable-2.22'

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Learn more about backports at https://docs.nextcloud.com/server/stable/go.php?to=developer-backports.