Update tests.md (#210)

exercises/shared/.docs/tests.md

@@ -5,4 +5,4 @@ To run the tests for an exercise, simply execute the `test_<exercise_name>.R` sc
 
 This can be conveniently done with [testthat's `auto_test` function](https://testthat.r-lib.org/reference/auto_test.html). Because exercism code and tests are in the same folder, use this same path for both `code_path` and `test_path` parameters. On the command-line, you can also run `Rscript test_<exercise_name>.R`.
 
-See the [tests page](https://exercism.org/tracks/r/tests) for more information.
+See the [tests page](https://exercism.org/docs/tracks/r/tests) for more information.