Remove unnecessary trailing / in prepare-docs.sh (#5323)

Co-authored-by: Ernesto García <ernestognw@gmail.com>

scripts/prepare-docs.sh

@@ -18,7 +18,7 @@ examples_source_dir="contracts/mocks/docs"
 examples_target_dir="docs/modules/api/examples"
 
 for f in "$examples_source_dir"/**/*.sol; do
-  name="${f/#"$examples_source_dir/"/}"
+  name="${f/#"$examples_source_dir"/}"
   mkdir -p "$examples_target_dir/$(dirname "$name")"
   sed -Ee '/^import/s|"(\.\./)+|"@openzeppelin/contracts/|' "$f" > "$examples_target_dir/$name"
 done