[ci] Set temporary directory for prefix using mktemp (closes #434)

.gitlab-ci.yml

@@ -9,8 +9,7 @@ py27-linux:
   - cd src/cpulimit && make && cd -
   - cd bin && ln -s ../src/cpulimit/src/cpulimit . && cd -
   - export COVERAGE_FILE=.coverage.django
-  - export BEAT_TEST_PREFIX=/var/tmp/test_prefix
-  - rm -rf $BEAT_TEST_PREFIX
+  - export BEAT_TEST_PREFIX=`mktemp -d --tmpdir=/var/tmp beat_test_prefix.XXXXXXXXX`
   - ./bin/coverage run --source='./beat/web' ./bin/django test --settings=beat.web.settings.test -v 2
   - export BEAT_CMDLINE_TEST_PLATFORM=django://beat.web.settings.test
   - export COVERAGE_FILE=.coverage.cmdline
@@ -18,6 +17,7 @@ py27-linux:
   - export NOSE_COVER_PACKAGE=beat.web
   - ./bin/nosetests -sv beat.cmdline
   - unset COVERAGE_FILE
+  - rm -rf $BEAT_TEST_PREFIX
   - unset BEAT_TEST_PREFIX
   - ./bin/coverage combine .coverage.django .coverage.cmdline
   - ./bin/coverage report