bump pytest-xdist to 1.22.5 (#6253)

Signed-off-by: Yoan Blanc <yoan.blanc@exoscale.ch>

tox.ini

@@ -64,6 +64,7 @@ source_paths =
     tests/lock_test.py
 
 [testenv]
+passenv = TRAVIS
 commands =
     {[base]install_and_test} {[base]all_packages}
     python tests/lock_test.py
@@ -121,7 +122,6 @@ commands =
 
 [testenv:cover]
 basepython = python2.7
-passenv = NUMPROCESSES
 commands =
     {[base]install_packages}
     ./tox.cover.sh
@@ -166,7 +166,9 @@ commands =
     docker run --rm -it apache-compat -c apache.tar.gz -vvvv
 whitelist_externals =
     docker
-passenv = DOCKER_*
+passenv =
+    DOCKER_*
+    TRAVIS
 
 [testenv:nginx_compat]
 commands =
@@ -175,7 +177,9 @@ commands =
     docker run --rm -it nginx-compat -c nginx.tar.gz -vv -aie
 whitelist_externals =
     docker
-passenv = DOCKER_*
+passenv =
+    DOCKER_*
+    TRAVIS
 
 [testenv:le_auto_precise]
 # At the moment, this tests under Python 2.7 only, as only that version is
@@ -185,7 +189,9 @@ commands =
     docker run --rm -t -i lea
 whitelist_externals =
     docker
-passenv = DOCKER_*
+passenv =
+    DOCKER_*
+    TRAVIS
 
 [testenv:le_auto_trusty]
 # At the moment, this tests under Python 2.7 only, as only that version is
@@ -198,6 +204,7 @@ whitelist_externals =
     docker
 passenv =
     DOCKER_*
+    TRAVIS
     TRAVIS_BRANCH
 
 [testenv:le_auto_wheezy]