Closes #143 add exposure response data

[jeffreyad]

Pull Request

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[Kcdahn]

Could ADEE (at this point) use, add a 1 or 2 brief intro sentences to explain it (like the ADES and ADTRR sections do below)?

[Kcdahn]

No further comments.

[github-actions]

The website is available at https://pharmaverse.github.io/examples/143-add-exposure-response-data.

[rossfarrugia]

Jeff needs this for his PHUSE US talk so i'm going to get it merged as Kristin has reviewed, and if any further comments for this example we can always make new issues later.