docs/gpu: ci: update flake tests requirements

Update the documentation to specify linking to a relevant GitLab
issue or email report for each new flake entry. Added specific
GitLab issue urls for amdgpu, i915, msm and xe driver.

Acked-by: Maxime Ripard <mripard@kernel.org>
Acked-by: Rodrigo Vivi <rodrigo.vivi@intel.com> #intel and xe
Acked-by: Abhinav Kumar <quic_abhinavk@quicinc.com> # msm
Acked-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org> # msm
Signed-off-by: Vignesh Raman <vignesh.raman@collabora.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Helen Koike <helen.koike@collabora.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240930095255.2071586-1-vignesh.raman@collabora.com