Error: Expected end of file after end of generated quantities block

rstan/StanHeaders v2.26.7 (Update `rstan`/`StanHeaders` packages v2.26.7 · stan-dev/r-packages@f752a4f · GitHub) is ready for testing:

remove.packages(c("rstan", "StanHeaders"))
install.packages("StanHeaders", repos = c("https://mc-stan.org/r-packages/", getOption("repos")))
install.packages("rstan", repos = c("https://mc-stan.org/r-packages/", getOption("repos")))