DuckSay: Explicitly call ddg_spice_duck_say()

Similar to Stopwatch or Timer or Flash, we need to call the JS function explicitly since they don't have endpoints that call them.
DuckSay: Append the title of the joke in the bubble.
Merge pull request #1110 from duckduckgo/jag/ducksay

DuckSay: Explicitly call ddg_spice_duck_say()