docs: link to @std/fs exists from file-existence example#3054

nielskaspers wants to merge 1 commit intodenoland:maindenoland/docs:mainfrom

nielskaspers:docs/3052-link-std-fs-checking-file-existencenielskaspers/docs:docs/3052-link-std-fs-checking-file-existenceCopy head branch name to clipboard