As mentioned in #17871 the current example can hide the fact that the module
path plays an important role. The example's explanation is expanded.
Moreover, the verb "attach" is replaced with "map" to make the vocabulary
consistent with the wording in the documentation of the terraform state.
Based on feedback from #15569 that the previous example was too abstract
and did not give enough context about what each of the different arguments
mean and how they generalize to other resource types.
Pam Selle