Fix 2001/anonymous/try.me.sh

For some reason the check that exists has opposite meanings in macOS and
linux so instead of checking the status of make I check if the file
exists after a make clobber all.

2001/anonymous/try.me.sh

@@ -1,8 +1,8 @@
 #!/usr/bin/env bash
 
-make clobber >/dev/null 2>&1
+make clobber all >/dev/null 2>&1
 
-if [[ $(make anonymous.ten >/dev/null 2>&1) ]]; then
+if [[ -f "anonymous.ten" ]]; then
 
     make anonymous 2>/dev/null
     echo "$ cp anonymous.ten anonymous.ten.bak" 1>&2