Release v0.17.5 on CRAN

Changes since v0.17.4

• Support keyword arguments for Callables. Fix #165.
• Add workaround for Julia 1.6+ on mac. Thank JackDunnNZ.
• Use use knitr::sew() instead of deprecated knitr::wrap(). Thank Kevin Cazelles.
• Update install_julia to use official releases rather than Julia_jll. Thank JackDunnNZ.
• Add support for macaarch64 to install_julia. Thank JackDunnNZ.
• Fix warnings caused by pkg macro usage.

Great thanks to @JackDunnNZ.