fix: replace a link at a standalone copy's name

A link already at the destination was skipped without a word and counted
as "dir not found" while the folder existed, so the emulator kept the file
the link pointed at. The link now gives way to the file, written beside it
and renamed over the name, and a name leading out of the folder is a named
failure.

install.sh

@@ -18,7 +18,7 @@ esac
 TEMP_INSTALLER=""
 TEMP_DIRECTORY=""
 DEFAULT_INSTALL_URL="https://raw.githubusercontent.com/Abdess/retrobios/main/install.py"
-DEFAULT_INSTALL_SHA256="007fffece97716aa9e1ed0606a8453f2da8a1262711aa68ca910673956b2b341"
+DEFAULT_INSTALL_SHA256="df46e48289c89c5c542095b01c16208ef54696df472685c99327e5022fcd7ab8"
 MAX_INSTALLER_BYTES=2097152
 
 cleanup() {