fix(AppAPIService): encode query parameter arrays via http_build_query

[edward-ly]

Resolves #384. If the checks still pass and this gets merged, perhaps we should take a look at other apps to see if they need to be updated in the same way.

[andrey18106]

LGTM, better also to double check within the issue to confirm it works as expected now.

[bigcat88]

let's merge this and request backports.

I'll test it heavily this week with Flow and Visionatrix, after that we can approve & merge backports.

[bigcat88]

/backport to stable29

[backportbot]

The backport to stable29 failed. Please do this backport manually.

# Switch to the target branch and update it
git checkout stable29
git pull origin stable29

# Create the new backport branch
git checkout -b backport/412/stable29

# Cherry pick the change from the commit sha1 of the change against the default branch
# This might cause conflicts, resolve them
git cherry-pick 2b307976

# Push the cherry pick commit to the remote repository and open a pull request
git push origin backport/412/stable29

Error: Failed to cherry pick commits: error: no cherry-pick or revert in progress
fatal: cherry-pick failed

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