Acceptance test suite performs poorly on poor network because of reverse lookups of interfaces addresses

Acceptance test suite runs many times slower when networking is bad, it turns out we do address lookups when detecting the environment:

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#0 0x00007ffff71a56e0 in __read_nocancel () at ../sysdeps/unix/syscall-template.S:81
#1 0x00007ffff7134a48 in _IO_new_file_underflow (fp=0x6912a0) at fileops.c:621
#2 0x00007ffff71359ee in _GI_IO_default_uflow (fp=0x6912a0) at genops.c:436
#3 0x00007ffff7129354 in _GI_IO_getline_info (fp=fp@entry=0x6912a0, buf=buf@entry=0x7ffffffe70a0 "", n=255, delim=delim@entry=10,
extract_delim=extract_delim@entry=1, eof=eof@entry=0x0) at iogetline.c:69
#4 0x00007ffff7129448 in _GI_IO_getline (fp=fp@entry=0x6912a0, buf=buf@entry=0x7ffffffe70a0 "", n=<optimized out>, delim=delim@entry=10,
extract_delim=extract_delim@entry=1) at iogetline.c:38
#5 0x00007ffff71282af in _IO_fgets (buf=0x7ffffffe70a0 "", n=<optimized out>, fp=0x6912a0) at iofgets.c:56
#6 0x00007ffff52431fc in ?? () from /lib/libnss_mdns4.so.2
#7 0x00007ffff5243932 in _nss_mdns4_gethostbyaddr_r () from /lib/libnss_mdns4.so.2
#8 0x00007ffff71cd1fb in __gethostbyaddr_r (addr=addr@entry=0x7ffffffe756c, len=len@entry=4, type=type@entry=2, resbuf=resbuf@entry=0x7ffff747fe20 <resbuf.11986>,
buffer=0x687e30 "\nddi", buflen=buflen@entry=1024, result=result@entry=0x7ffffffe7400, h_errnop=h_errnop@entry=0x7ffffffe73f0) at ../nss/getXXbyYY_r.c:263
#9 0x00007ffff71ccf92 in gethostbyaddr (addr=0x7ffffffe756c, len=4, type=2) at ../nss/getXXbyYY.c:116
#10 0x00007ffff796c0a8 in GetInterfacesInfo (ctx=0x659010) at unix_iface.c:430
#11 0x00007ffff796a35b in DetectEnvironment (ctx=0x659010, use_monitoring_data=true, use_name_info=true) at sysinfo.c:2637
#12 0x00007ffff791b39c in GenericAgentDiscoverContext (ctx=0x659010, config=0x6598e0) at generic_agent.c:119
#13 0x00000000004099aa in main (argc=2, argv=0x7fffffffdf28) at cf-agent.c:233
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