Fix thisroot.sh to properly remove previous ROOT version from paths

The second call to drop_from_path was using the original path variable
instead of $newpath (result of first call), causing only the last
transformation to be applied. This affected LD_LIBRARY_PATH,
DYLD_LIBRARY_PATH, SHLIB_PATH, LIBPATH, and PYTHONPATH.

Fixes the issue where old_rootsys/lib was not being removed when
switching ROOT versions.

Co-authored-by: pcanal <[email protected]>

Author: Copilot

config/thisroot.sh

@@ -39,27 +39,27 @@ clean_environment()
       fi
       if [ -n "${LD_LIBRARY_PATH-}" ]; then
          drop_from_path "$LD_LIBRARY_PATH" "${old_rootsys}/lib"
-         drop_from_path "$LD_LIBRARY_PATH" "${old_rootsys}/lib/root"
+         drop_from_path "$newpath" "${old_rootsys}/lib/root"
          LD_LIBRARY_PATH=$newpath
       fi
       if [ -n "${DYLD_LIBRARY_PATH-}" ]; then
          drop_from_path "$DYLD_LIBRARY_PATH" "${old_rootsys}/lib"
-         drop_from_path "$DYLD_LIBRARY_PATH" "${old_rootsys}/lib/root"
+         drop_from_path "$newpath" "${old_rootsys}/lib/root"
          DYLD_LIBRARY_PATH=$newpath
       fi
       if [ -n "${SHLIB_PATH-}" ]; then
          drop_from_path "$SHLIB_PATH" "${old_rootsys}/lib"
-         drop_from_path "$SHLIB_PATH" "${old_rootsys}/lib/root"
+         drop_from_path "$newpath" "${old_rootsys}/lib/root"
          SHLIB_PATH=$newpath
       fi
       if [ -n "${LIBPATH-}" ]; then
          drop_from_path "$LIBPATH" "${old_rootsys}/lib"
-         drop_from_path "$LIBPATH" "${old_rootsys}/lib/root"
+         drop_from_path "$newpath" "${old_rootsys}/lib/root"
          LIBPATH=$newpath
       fi
       if [ -n "${PYTHONPATH-}" ]; then
          drop_from_path "$PYTHONPATH" "${old_rootsys}/lib"
-         drop_from_path "$PYTHONPATH" "${old_rootsys}/lib/root"
+         drop_from_path "$newpath" "${old_rootsys}/lib/root"
          PYTHONPATH=$newpath
       fi
       if [ -n "${MANPATH-}" ]; then