Remove duplicate R versions with older compilers

Matthew K Defenderfer
2024-06-03T14:20:27-05:00

Removed R versions with outdated compiler toolchains that had newer versions installed. This will help alleviate some package installation issues by limiting users to only modules with newer toolchains (in the case of R 3.6.2 and above). The default R version was also changed to `R/4.2.0-foss-2022b`.

Closes #14