HTTPS access to eulake when XCache is XRootD 5.1

When the XCache is on XRootD 5.1, it's impossible to do file transfer from the EOS instance at CERN (EULAKE)

According to Elvin (EOS dev) and Andy (XRootD dev), it could come from known bugs (https://github.com/xrootd/xrootd/issues/1399 and ). Both have corrective patch which needs to be deploy on EOS (https://github.com/xrootd/xrootd/commit/d74e7a8af67e83fad14c3cbf08a58843f897b957 and https://github.com/xrootd/xrootd/pull/1408 or https://github.com/xrootd/xrootd/pull/1412).

If it the one about range, Wei Yang advise to start the server with the environment variable XRDCLHTTP_AVOIDRANAGE set to 1