[RW-3668][risk=no] Link data dictionary doc to sidebar (#2754)
[RW-3668][risk=no] Link data dictionary doc to sidebar (#2754)

* RW-3668 link data dictionary icon to google doc

* RW-3668 add title tags to sidebar icons

all-of-us/workbench,all-of-us/workbench,all-of-us/workbench,all-of-us/workbench,all-of-us/workbench,all-of-us/workbench,all-of-us/workbench,all-of-us/workbench,all-of-us/workbench