tests: change default http_max_conns_per_client to 250 to ease tests (#7625)
tests: change default http_max_conns_per_client to 250 to ease tests (#7625)

On recent Mac OS versions, the ulimit defaults to 256 by default, but many
systems (eg: some Linux distributions) often limit this value to 1024.

On validation of configuration, Consul now validates that the number of
allowed files descriptors is bigger than http_max_conns_per_client.

This make some unit tests failing on Mac OS.
Use a less important value in unit test, so tests runs well by default
on Mac OS without need for tuning the OS.
hashicorp/consul,hashicorp/consul,hashicorp/consul,hashicorp/consul