Set RSPM_ROOT, can be removed after remotes 2.4.3 release

Author: timoast

.github/workflows/cmd-check.yml

@@ -112,7 +112,7 @@ jobs:
       - name: Install Linux system dependencies
         if: runner.os == 'Linux'
         run: |
-          sysreqs=$(Rscript -e 'cat("apt-get update -y && apt-get install -y", paste(gsub("apt-get install -y ", "", remotes::system_requirements("ubuntu", "20.04")), collapse = " "))')
+          sysreqs=$(Rscript -e 'Sys.setenv(RSPM_ROOT = "https://packagemanager.posit.co"); cat("apt-get update -y && apt-get install -y", paste(gsub("apt-get install -y ", "", remotes::system_requirements("ubuntu", "20.04")), collapse = " "))')
           echo $sysreqs
           sudo -s eval "$sysreqs"