Add StarSearch Share to Changelog

[BekahHW]

We now have a share feature with OG image for StarSearch. Let's add this to the changelog and get to sharing!

[BekahHW]

@isabensusan are you working on this?

[nickytonline]

Can we hold off on this one until after tomorrow's release? We're just making some changes to sharing to accommodate the new StarSearch thread history that's coming, i.e. open-sauced/app#3551

[BekahHW]

@nickytonline for sure. There's currently no copy or assets. I just want to keep track so we can add it to the Changelog when the feature is ready.