Bumped touchstone reqs

[VisruthSK]

Latest R and LTS ubuntu

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 92.80%. Comparing base (57bd12a) to head (70a04ed).

Additional details and impacted files

@@           Coverage Diff           @@
##           master     #358   +/-   ##
=======================================
  Coverage   92.80%   92.80%           
=======================================
  Files          31       31           
  Lines        3004     3004           
=======================================
  Hits         2788     2788           
  Misses        216      216           

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[github-actions]

This is how benchmark results would change (along with a 95% confidence interval in relative change) if 70a04ed is merged into master:

• ✔️loo_function: 2.18s -> 2.17s [-2%, +1.29%]
• ✔️loo_matrix: 1.67s -> 1.66s [-2.48%, +0.21%]
  Further explanation regarding interpretation and methodology can be found in the documentation.

[VisruthSK]

Yay sticky comments work!