Etag header is not returned with PUT request (async uploads enabled)

[saw-jan]

Steps to reproduce

1. Start oCIS with async uploads enabled: STORAGE_USERS_OCIS_ASYNC_UPLOADS=true (and with OCIS_INSECURE=true until Fix Postprocessing service #5269)
2. Upload a file

curl -XPUT "https://localhost:9200/remote.php/webdav/lorem.txt" -d"uploaded" -uadmin:admin -vk

< HTTP/1.1 201 Created
< Access-Control-Allow-Origin: *
< Content-Length: 0
< Content-Security-Policy: default-src 'none';
< Date: Thu, 22 Dec 2022 08:20:29 GMT
< Oc-Fileid: 88a1e29d-dd38-46c7-b1fc-582996e9f0d1$612f56c1-05cd-4b4c-85a8-4de7b51f3048!49286ae7-df90-4745-a69d-7614a458c69d
< X-Content-Type-Options: nosniff
< X-Download-Options: noopen
< X-Frame-Options: SAMEORIGIN
< X-Permitted-Cross-Domain-Policies: none
< X-Robots-Tag: none
< X-Xss-Protection: 1; mode=block
<

Expected behavior

To return Etag headers like with async uploads disabled

< HTTP/1.1 201 Created
< Access-Control-Allow-Origin: *
< Content-Length: 0
< Content-Security-Policy: default-src 'none';
< Date: Thu, 22 Dec 2022 08:50:49 GMT
< Etag: "b7290599f9055d004426bc3015b96347"
< Oc-Etag: "b7290599f9055d004426bc3015b96347"
< Oc-Fileid: 88a1e29d-dd38-46c7-b1fc-582996e9f0d1$612f56c1-05cd-4b4c-85a8-4de7b51f3048!b173f770-14cd-4eb4-9db7-b8ee799eeede
< X-Content-Type-Options: nosniff
< X-Download-Options: noopen
< X-Frame-Options: SAMEORIGIN
< X-Permitted-Cross-Domain-Policies: none
< X-Robots-Tag: none
< X-Xss-Protection: 1; mode=block
< 

Actual behavior

No Etag headers

[saw-jan]

Fixed in PR cs3org/reva#3571