Remove dead modify_aes_() and fix deprecated size usage in helpers#446

jgabry merged 2 commits intostan-dev:masterstan-dev/bayesplot:masterfrom

ishaan-arora-1:fix/deprecated-size-and-dead-code-444-445ishaan-arora-1/bayesplot:fix/deprecated-size-and-dead-code-444-445Copy head branch name to clipboard