Proofreading: network.protocol.* definition is different between HTTP metrics and spans

[lmolkova]

metrics:

network.protocol.name	string	OSI Application Layer or non-OSI equivalent. The value SHOULD be normalized to lowercase.	amqp; http; mqtt	Recommended
network.protocol.version	string	Version of the application layer protocol used. See note below. [4]	3.1.1	Recommended

spans:

network.protocol.name	string	OSI Application Layer or non-OSI equivalent. The value SHOULD be normalized to lowercase.	http; spdy	Recommended: if not default (http).
network.protocol.version	string	Version of the application layer protocol used. See note below. [6]	1.0; 1.1; 2; 3	Recommended

Probably something went wrong with semconvgen and yaml, waiting for semconvgen 0.22.0 (and open-telemetry/build-tools#204) to fix it