1) I installed gnome-dictionary
2) As I had already upgraded the yaru packages to verify another fix I downgraded them
3) I verified the icon was as per comment #1
4) I upgraded the packages to version 20.04.7 by enabling -proposed
5) I verified that the icon had changed as per the link in comment #2
To verify the fix I took the following steps:
1) I installed gnome-dictionary
2) As I had already upgraded the yaru packages to verify another fix I downgraded them
3) I verified the icon was as per comment #1
4) I upgraded the packages to version 20.04.7 by enabling -proposed
5) I verified that the icon had changed as per the link in comment #2
So marking as verified