asv errors on desktop

[Chris Warburton]

Looks like an obvious issue with jq not being in the environment:

"Setting default memory limit of 2GB\nNo cluster count given; using 1
(sqrt of sample size)\nCalculating SHA256 checksums of
names\n/nix/store/cj83n3yg86zpvk9wi77dbr6myvi9aq12-explore-theories: line 20: jq: command not
found\ngrep: write error\nreduce-equations: Failed to parse eqs: not
enough input\n

Also, when exploration gets killed there might be a more graceful way to
handle it, e.g. setting 'success' to False:

"Setting default memory limit of 2GB\nNo cluster count given; using 1
(sqrt of sample size)\nCalculating SHA256 checksums of
names\nrunghcXXXX1804289383846930886.hs:
runghcXXXX1804289383846930886.hs: signal: 15\nMEM CPU 14.97 MEM 2035168
MAXMEM 2035168 STALE 0 MAXMEM_RSS 837336\n<time
name=\"ALL\">13930</time>\nreduce-equations: Failed to parse eqs: not
enough input\n"