Fix code-server.sh script on macOS

ci/code-server.sh

@@ -1,6 +1,18 @@
 #!/usr/bin/env sh
-# code-server.sh -- Run code-server with the bundled Node binary.
+# Runs code-server with the bundled Node binary.
 
-dir="$(dirname "$(readlink -f "$0" || realpath "$0")")"
+# More complicated than readlink -f or realpath to support macOS.
+# See https://github.com/cdr/code-server/issues/1537
+get_installation_dir() {
+  # We read the symlink, which may be relative from $0.
+  dst="$(readlink "$0")"
+  # We cd into the $0 directory.
+  cd "$(dirname "$0")"
+  # Now we can cd into the dst directory.
+  cd "$(dirname "$dst")"
+  # Finally we use pwd -P to print the absolute path of the directory of $dst.
+  pwd -P
+}
 
+dir=$(get_installation_dir)
 exec "$dir/node" "$dir/out/node/entry.js" "$@"