[PULL 21/23] Acceptance tests: do not try to reuse packages from the system

[Cleber Rosa <crosa@redhat.com>]

The premise behind the original behavior is that it would save people
from downloading Avocado (and other dependencies) if already installed
on the system.  To be honest, I think it's extremely rare that the
same versions described as dependencies will be available on most
systems.  But, the biggest motivations here are that:

 1) Hacking on QEMU in the same system used to develop Avocado leads
    to confusion with regards to the exact bits that are being used;

 2) Not reusing Python packages from system wide installations gives
    extra assurance that the same behavior will be seen from tests run
    on different machines;

With regards to downloads, pip already caches the downloaded wheels
and tarballs under ~/.cache/pip, so there should not be more than
one download even if the venv is destroyed and recreated.

Signed-off-by: Cleber Rosa <crosa@redhat.com>
Message-Id: <20210415215141.1865467-3-crosa@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Willian Rampazzo <willianr@redhat.com>
Reviewed-by: Wainer dos Santos Moschetta <wainersm@redhat.com>
Signed-off-by: Cleber Rosa <crosa@redhat.com>
---
 tests/Makefile.include | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tests/Makefile.include b/tests/Makefile.include
index e4dcb17329..6e16c05f10 100644
--- a/tests/Makefile.include
+++ b/tests/Makefile.include
@@ -96,7 +96,7 @@ AVOCADO_TAGS=$(patsubst %-softmmu,-t arch:%, $(filter %-softmmu,$(TARGETS)))
 
 $(TESTS_VENV_DIR): $(TESTS_VENV_REQ)
 	$(call quiet-command, \
-            $(PYTHON) -m venv --system-site-packages $@, \
+            $(PYTHON) -m venv $@, \
             VENV, $@)
 	$(call quiet-command, \
             $(TESTS_VENV_DIR)/bin/python -m pip -q install -r $(TESTS_VENV_REQ), \
-- 
2.31.1