drm/doc: ci: Add IGT version details for flaky tests

Document the IGT version in the flaky tests reporting template.

Acked-by: Helen Koike <helen.koike@collabora.com>
Signed-off-by: Vignesh Raman <vignesh.raman@collabora.com>
Signed-off-by: Helen Koike <helen.koike@collabora.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20231207091831.660054-10-vignesh.raman@collabora.com