upload failure message when disk full

[wkloucek]

Describe the bug

when uploading a file on a oCIS instance with full disk we don't have a speaking error message.

Steps to reproduce

Steps to reproduce the behavior:

1. have an oCIS instance
2. have your disk full
3. upload a file larger than the remaining free disk space

Expected behavior

Have an error message: "upload failed because not sufficient space on the target system"

Actual behavior

error message: "upload failed"

The log says:
{"level":"error","service":"storage-users","pkg":"rgrpc","traceid":"00000000000000000000000000000000","error":"error: insufficient storage: disk full","status":{"code":19,"message":"insufficient storage","trace":"00000000000000000000000000000000"},"time":"2022-05-11T11:58:59Z","message":"failed to initiate upload"}

Setup

oCIS 2.0.0-beta1 on a server with constrained disk

[pascalwengerter]

If OCIS responds with e.g. a 507 we could check for that in web and then render (translated) strings to the UI, which AFAIK the backend is not able to

[dragonchaser]

There is a PR on reva: cs3org/reva#2891 to fix this.
@pascalwengerter a 507 is returned as soon as said PR is merged, I thin kthis needs handling in the UI.