GH-47821: [CI][Release][R] Add backslash to repo folder for R binary testing and remove libarrow subfolder

Author: raulcd

dev/tasks/macros.jinja

@@ -244,15 +244,15 @@ env:
     uses: actions/download-artifact@v4
     with:
       name: r-libarrow-windows-x86_64
-      path: repo/libarrow
+      path: repo
   {% endif %}
   {% if get_nix %}
     {% for openssl_version in ["1.0", "1.1", "3.0"] %}
   - name: Get Linux OpenSSL {{ openssl_version }} binary
     uses: actions/download-artifact@v4
     with:
       name: r-libarrow-linux-x86_64-openssl-{{ openssl_version }}
-      path: repo/libarrow
+      path: repo
     {% endfor %}
   {% endif %}
   {% if get_mac %}
@@ -262,7 +262,7 @@ env:
     uses: actions/download-artifact@v4
     with:
       name: r-libarrow-darwin-{{ arch }}-openssl-{{ openssl_version }}
-      path: repo/libarrow
+      path: repo
       {% endfor %}
     {% endfor %}
   {% endif %}
@@ -285,7 +285,7 @@ env:
     shell: Rscript {0}
     run: |
       profile_path <- file.path(getwd(), ".Rprofile")
-      repo <- paste0("file://", getwd(), "/repo")
+      repo <- paste0("file://", getwd(), "/repo/")
       str <- paste0("options(arrow.repo = '", repo, "' )")
       print(str)
       write(str, file = profile_path, append = TRUE)

dev/tasks/r/github.packages.yml

@@ -257,7 +257,7 @@ jobs:
           LIBARROW_BINARY: "true" # has to be set as long as allowlist not updated
           LIBARROW_BUILD: "false"
           ARROW_R_ENFORCE_CHECKSUM: "true"
-          ARROW_R_CHECKSUM_PATH: "{{ '${{ github.workspace }}' }}/repo/libarrow"
+          ARROW_R_CHECKSUM_PATH: "{{ '${{ github.workspace }}' }}/repo"
         run: |
           on_windows <- tolower(Sys.info()[["sysname"]]) == "windows"
 
@@ -346,7 +346,7 @@ jobs:
           LIBARROW_BUILD: "FALSE"
           LIBARROW_BINARY: {{ '${{ matrix.config.libarrow_binary }}' }}
           ARROW_R_ENFORCE_CHECKSUM: "true"
-          ARROW_R_CHECKSUM_PATH: "{{ '${{ github.workspace }}' }}/repo/libarrow"
+          ARROW_R_CHECKSUM_PATH: "{{ '${{ github.workspace }}' }}/repo"
         shell: bash
         run: |
           Rscript -e '