Add change log entry for SSM documentation

Add change log entries to explain changes from !274 (merged).

We need this before we can do our next release.

assigned to @bhooshan.gadre and @sushant.sharma-chaudhary

@bhooshan.gadre, would you please complete this as soon as possible so that this is not a bottleneck to publishing SSM candidates? Please add a change log entry to !294 (merged).

created branch 399-add-change-log-entry-for-ssm-documentation to address this issue

mentioned in merge request !299 (closed)