Usage of deprecated naming of span attributes

[onyn]

Nginx-otel module defines several span attributes . Almost all of them deprecated according to opentelemetry docs (http, network).

Actual labels:

• http.method -> http.request.method
• http.target -> url.path + url.query
• http.route -> left intact
• http.scheme -> url.scheme
• http.flavor -> network.protocol.name + network.protocol.version
• http.user_agent -> user_agent.original
• http.request_content_length -> http.request.header.content-length
• http.response_content_length -> http.response.header.content-length
• http.status_code -> http.response.status_code
• net.host.name -> server.address
• net.host.port -> server.port
• net.sock.peer.addr -> network.peer.address
• net.sock.peer.port -> network.peer.port