* docs: update AWS examples. Disntinguish between alb and alb listener datasource
* more hcl highlighting
* more hcl
* fix missing end quote in docs
* docs: finish updates to AWS data source highlights
Also updates layout to distinguish some resources
The primary purpose of this data source is to ask the question "what is
my current region?", but it can also be used to retrieve the endpoint
hostname for a particular (possibly non-current) region, should that be
useful for some esoteric case.