Fix sbin/ping/ping_test to be executed in parallel mode

[olivier]

Summary

All ping tests are using the same filename std.out, that could create conflict if executed with parallelism enabled: switching to a dedicated filename.

[asomers]

It shouldn't matter that they're using the same file name, because Kyua runs each test case in a separate temporary directory. Also, when you use Phabricator please include full context . The best way to do that is to create your revisions using arcanist (available in ports as devel/arcanist-php*. Or if you're uploading diffs through the web interface, generate them using the -u 9999 option.

[olivier]

You've right, after more tests on my side, the failing in parallel mode is not due to that.
For history, here is the error message that happen sometime:

sbin.ping.ping_test.ping6_c1_s8_t1 (from (test-report.xml))

Failing for the past 1 build (Since Unstable#3432 )
Took 0.14 sec.
add description
Error Message
atf-check failed; see the output of the test for details
Standard Output
Executing command [ ping6 -c 1 -s 8 -t 1 localhost ]
Standard Error
Test case metadata
------------------

allowed_architectures is empty
allowed_platforms is empty
description = Use IPv6 when invoked as ping6
has_cleanup = false
is_exclusive = false
required_configs is empty
required_disk_space = 0
required_files is empty
required_memory = 0
required_programs is empty
required_user is empty
timeout = 300

Timing information
------------------

Start time: 2021-03-16T23:47:15.823694Z
End time:   2021-03-16T23:47:15.970485Z
Duration:   0.147s

Original stderr
---------------

Fail: stderr not empty
--- /dev/null	2021-03-16 23:47:15.844224000 +0000
+++ /tmp/kyua.B7Ti7l/20/work/check.5SpFi3/stderr	2021-03-16 23:47:15.841696000 +0000
@@ -0,0 +1 @@
+ping6: failed to get receiving hop limit