Docs: Fix incorrect project version generation.

The documentation version generates differently in the local
and CI building environments. The expectation is to have the version
in the form of "v1.5.0+(last commit SHA)" while CI makes it v1.5.0.

Signed-off-by: Anton Komlev <anton.komlev@arm.com>
Change-Id: Ia989c1c169a614e169f1defdaa3ca34c4e0cf643
3 files changed