Location header is incorrect in a response on LCM operation

According to clause 5.4 of ETSI NFV-SOL003 V2.6.1 [1], VNFM should return a response
with a "Location" HTTP header during a VNF LCM operation, but it is found that some
LCMs don't meet it.

For example, the following is the part of the debug log during an Instantiate operation.
RESP message should contain "Location" header, but is actually lost.

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REQ: curl -g -i -X POST http://192.168.122.241:9890/vnflcm/v1/vnf_instances/afc0e950-57d7-40b0-a09c-af645e1af057/instantiate -H "Accept: application/json" -H "Content-Type: application/json" -H "User-Agent: python-tackerclient" -H "X-Auth-Token: {SHA256}40b4c06698a995af8dc1991c1eb6a1819d14eada01ab2d1ae35a384bd52148d9" -d '{"flavourId": "simple"}'
Starting new HTTP connection (1): 192.168.122.241:9890
http://192.168.122.241:9890 "POST /vnflcm/v1/vnf_instances/afc0e950-57d7-40b0-a09c-af645e1af057/instantiate HTTP/1.1" 202 0
RESP: [202] Connection: keep-alive Content-Length: 0 Content-Type: application/json Date: Wed, 13 Jan 2021 09:29:24 GMT X-Openstack-Request-Id: req-d72b2d5f-6caf-40a1-b66a-39ab38dbb6e3
POST call to nfv-orchestration for http://192.168.122.241:9890/vnflcm/v1/vnf_instances/afc0e950-57d7-40b0-a09c-af645e1af057/instantiate used request id req-d72b2d5f-6caf-40a1-b66a-39ab38dbb6e3
Instantiate request for VNF Instance afc0e950-57d7-40b0-a09c-af645e1af057 has been accepted.
clean_up InstantiateVnfLcm:
END return value: 0

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[1] https://www.etsi.org/deliver/etsi_gs/NFV-SOL/001_099/003/02.06.01_60/gs_NFV-SOL003v020601p.pdf