[pygobject] gitlab-ci: switch to a non-srcdir build

[Christoph Reiter <creiter src gnome org>]

commit efb19909ebf15c8bdbd0b4acfe0046a512ba3b82
Author: Christoph Reiter <reiter christoph gmail com>
Date:   Sat Jan 20 12:22:41 2018 +0100

    gitlab-ci: switch to a non-srcdir build

 .gitlab-ci/test-docker.sh | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)
---
diff --git a/.gitlab-ci/test-docker.sh b/.gitlab-ci/test-docker.sh
index e0386b60..c371f715 100755
--- a/.gitlab-ci/test-docker.sh
+++ b/.gitlab-ci/test-docker.sh
@@ -13,8 +13,12 @@ export MALLOC_CHECK_=3
 export MALLOC_PERTURB_=$((${RANDOM} % 255 + 1))
 PYVER=$(python -c "import sys; sys.stdout.write(str(sys.version_info[0]))")
 
+SOURCE_DIR="$(pwd)"
+mkdir /tmp/build
+cd /tmp/build
+
 # BUILD
-./autogen.sh --with-python=python
+"${SOURCE_DIR}"/autogen.sh --with-python=python
 make
 
 # TESTS
@@ -23,6 +27,8 @@ xvfb-run -a make check
 # CODE QUALITY CHECKS
 make check.quality
 
+cd "${SOURCE_DIR}"
+
 # DOCUMENTATION CHECKS
 if [[ "${PYVER}" == "2" ]]; then
     python -m pip install sphinx sphinx_rtd_theme