[CI] tools_test sometimes ends up chdiring to root ("/")

Submitted by Martin Peres

Assigned to Tomi Sarvela

Link to original bug (#109352)

Description

https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_5388/shard-iclb2/igt@tools_test@sysfs_l3_parity.html

Using tools from /opt/igt/bin
[...]

https://intel-gfx-ci.01.org/tree/drm-tip/IGT_4761/shard-iclb2/igt@tools_test@sysfs_l3_parity.html

Using tools from /bin
[...]