CI: meta-arm success is reported in the FVP report

Kronos pipelines with meta-arm sibling pipelines were formerly not
checking meta-arm success, resulting in success shown in the FVP report
when the Kronos pipeline passed and meta-arm failed. This commit adds a
check of the meta-arm pipeline (in the case that one exists). The row
in the FVP report will now correctly show as red in the case that
either Kronos or meta-arm failed. There is a race condition introduced
between the meta-arm pipeline and the report being rendered. If the
meta-arm pipeline has not completed by the time the FVP report is
rendered, the row for the pipeline will be gray.

Older builds will never have the parent project ID variable to pass to
the pipeline so will ignore meta-arm's success in the report, however
these builds will be removed from Artifactory and the report in future
as per the retention policy and this change will apply to all future
builds.

Signed-off-by: Isaac Perry <isaac.perry@arm.com>