Adapt targets component to render on sdg help page

This component was rendered on different pages so there were no conflicts
with static id's.
Now in the SDG help page we are going to render them all at once, so we
convert the static identifiers to dynamic.

app/assets/stylesheets/sdg/goals/targets.scss

@@ -1,4 +1,4 @@
-.sdg-goal-show .targets {
+.sdg-goal-targets {
   dt,
   dd {
     display: inline;