Use pak to install pkg

Author: tomuben

.github/workflows/windows_macosx.yml

@@ -51,15 +51,9 @@ jobs:
         shell: Rscript {0}
         env:
           GITHUB_PAT: ${{ secrets.GITHUB_TOKEN }}
-      - name: Update deps #devtools::install() is unstable under windows. workaround is to run 'devtools::install_deps()' beforehand.
-        run: |
-          devtools::install_deps()
-        shell: Rscript {0}
-        env:
-          GITHUB_PAT: ${{ secrets.GITHUB_TOKEN }}
       - name: Build
         run: |
-          devtools::install()
+          pak::local_install(dependencies=TRUE)
         shell: Rscript {0}
         env:
           GITHUB_PAT: ${{ secrets.GITHUB_TOKEN }}