fix: keep_download condition

Fixes #1711

lib/functions/installs.bash

@@ -236,8 +236,8 @@ install_tool_version() {
     if [ $install_exit_code -eq 0 ] && [ $download_exit_code -eq 0 ]; then
       # Remove download directory if --keep-download flag or always_keep_download config setting are not set
       always_keep_download=$(get_asdf_config_value "always_keep_download")
-      if [ ! "$keep_download" = "true" ] && [ ! "$always_keep_download" = "yes" ]; then
-        if [ -d "$download_path" ]; then
+      if [ -d "$download_path" ]; then
+        if [ ! "$keep_download" = "true" ] && [ ! "$always_keep_download" = "yes" ]; then
           rm -r "$download_path"
         else
           printf '%s\n' "asdf: Warn: You have configured asdf to preserve downloaded files (with always_keep_download=yes or --keep-download). But" >&2