docs(changelog): changelog for lts-v2.8.13 release

Generated with the command:
npm run release -- --release-as 2.8.13

Signed-off-by: Yann Gautier <yann.gautier@st.com>
Change-Id: I225aa9d62da21ec6fa8c5c4a04491a5a2a73d39a
7 files changed