Add link to solutions, closes hadley#1555

Author: mine-cetinkaya-rundel

index.qmd

@@ -19,6 +19,8 @@ If you speak another language, you might be interested in the freely available t
 -   [Italian](https://it.r4ds.hadley.nz)
 -   [Turkish](https://tr.r4ds.hadley.nz)
 
+You can find suggested answers to exercises in the book at <https://mine-cetinkaya-rundel.github.io/r4ds-solutions>.
+
 Please note that R4DS uses a [Contributor Code of Conduct](https://contributor-covenant.org/version/2/0/CODE_OF_CONDUCT.html).
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