Do not remove stderr from pict output

Removing stderr from the pict tool serves no purpose and drops valuable
information, we might use when debugging failed pairwise CI job, such
as:

    Input Error: A parameter names must be unique

(cherry picked from commit 079debaa)
86 jobs for !4731 with mnowak/pairwise-pict-keep-stderr-v9_11 in 19 seconds (queued for 10 seconds)
latest detached
Status Job ID Name Coverage
  Precheck
canceled #1519726
amd64 linux
autoreconf

00:00:18

canceled #1519728
amd64 linux
clang-format

00:00:17

canceled #1519729
amd64 linux
coccinelle

00:00:16

canceled #1519730
amd64 linux
danger

00:00:13

canceled #1519727
amd64 linux
misc

00:00:17

 
  Build
canceled #1519745
amd64 linux
clang:asan

canceled #1519751
amd64 linux
clang:buster:amd64

canceled #1519753
amd64 libvirt
clang:freebsd11:amd64

canceled #1519754
amd64 libvirt
clang:freebsd12:amd64

canceled #1519755
amd64 libvirt
clang:openbsd:amd64

canceled #1519747
amd64 linux
clang:tsan

canceled #1519749
amd64 linux
clang:tsan:noatomics

canceled #1519731
amd64 linux
gcc:alpine3.12:amd64

canceled #1519744
amd64 linux
gcc:asan

canceled #1519737
amd64 linux
gcc:buster:amd64

canceled #1519733
amd64 linux
gcc:centos6:amd64

canceled #1519732
i386 linux
gcc:centos6:i386

canceled #1519734
amd64 linux
gcc:centos7:amd64

canceled #1519735
amd64 linux
gcc:centos8:amd64

canceled #1519741
amd64 linux
gcc:fedora33:amd64

canceled #1519743
amd64 linux
gcc:focal:amd64

canceled #1519750
amd64 linux
gcc:noatomics

canceled #1519739
amd64 linux
gcc:out-of-tree

canceled #1519752
amd64 linux
gcc:pkcs11

canceled #1519738
amd64 linux
gcc:sid:amd64

canceled #1519736
amd64 linux
gcc:stretch:amd64

canceled #1519746
amd64 linux
gcc:tsan

canceled #1519748
amd64 linux
gcc:tsan:noatomics

canceled #1519740
amd64 linux
gcc:tumbleweed:amd64

canceled #1519742
amd64 linux
gcc:xenial:amd64

canceled #1519757
amd64 windows
msvc:windows:amd64

00:00:18

canceled #1519756
amd64 linux
nolibtool:sid:amd64

 
  Unit
canceled #1519771
amd64 linux
unit:clang:asan

canceled #1519777
amd64 linux
unit:clang:buster:amd64

canceled #1519779
amd64 libvirt
unit:clang:freebsd11:amd64

canceled #1519780
amd64 libvirt
unit:clang:freebsd12:amd64

canceled #1519773
amd64 linux
unit:clang:tsan

canceled #1519775
amd64 linux
unit:clang:tsan:noatomics

canceled #1519758
amd64 linux
unit:gcc:alpine3.12:amd64

canceled #1519770
amd64 linux
unit:gcc:asan

canceled #1519764
amd64 linux
unit:gcc:buster:amd64

canceled #1519760
amd64 linux
unit:gcc:centos6:amd64

canceled #1519759
i386 linux
unit:gcc:centos6:i386

canceled #1519761
amd64 linux
unit:gcc:centos7:amd64

canceled #1519762
amd64 linux
unit:gcc:centos8:amd64

canceled #1519767
amd64 linux
unit:gcc:fedora33:amd64

canceled #1519769
amd64 linux
unit:gcc:focal:amd64

canceled #1519776
amd64 linux
unit:gcc:noatomics

canceled #1519778
amd64 linux
unit:gcc:pkcs11

canceled #1519765
amd64 linux
unit:gcc:sid:amd64

canceled #1519763
amd64 linux
unit:gcc:stretch:amd64

canceled #1519772
amd64 linux
unit:gcc:tsan

canceled #1519774
amd64 linux
unit:gcc:tsan:noatomics

canceled #1519766
amd64 linux
unit:gcc:tumbleweed:amd64

canceled #1519768
amd64 linux
unit:gcc:xenial:amd64

canceled #1519781
amd64 linux
unit:nolibtool:sid:amd64

 
  System
canceled #1519795
amd64 linux
system:clang:asan

canceled #1519801
amd64 linux
system:clang:buster:amd64

canceled #1519803
amd64 libvirt
system:clang:freebsd11:amd64

canceled #1519804
amd64 libvirt
system:clang:freebsd12:amd64

canceled #1519797
amd64 linux allowed to fail
system:clang:tsan

canceled #1519799
amd64 linux allowed to fail
system:clang:tsan:noatomics

canceled #1519782
amd64 linux
system:gcc:alpine3.12:amd64

canceled #1519794
amd64 linux
system:gcc:asan

canceled #1519788
amd64 linux
system:gcc:buster:amd64

canceled #1519784
amd64 linux
system:gcc:centos6:amd64

canceled #1519783
i386 linux
system:gcc:centos6:i386

canceled #1519785
amd64 linux
system:gcc:centos7:amd64

canceled #1519786
amd64 linux
system:gcc:centos8:amd64

canceled #1519791
amd64 linux
system:gcc:fedora33:amd64

canceled #1519793
amd64 linux
system:gcc:focal:amd64

canceled #1519800
amd64 linux
system:gcc:noatomics

canceled #1519802
amd64 linux
system:gcc:pkcs11

canceled #1519789
amd64 linux
system:gcc:sid:amd64

canceled #1519787
amd64 linux
system:gcc:stretch:amd64

canceled #1519796
amd64 linux allowed to fail
system:gcc:tsan

canceled #1519798
amd64 linux allowed to fail
system:gcc:tsan:noatomics

canceled #1519790
amd64 linux
system:gcc:tumbleweed:amd64

canceled #1519792
amd64 linux
system:gcc:xenial:amd64

canceled #1519805
amd64 linux
system:nolibtool:sid:amd64

 
  Docs
canceled #1519806
amd64 linux
docs

 
  Postcheck
canceled #1519810
amd64 linux
cppcheck

canceled #1519807
amd64 linux
flake8

canceled #1519811
amd64 linux
gcov

canceled #1519808
amd64 linux
pylint

canceled #1519809
amd64 linux
scan-build