Fix #924: Checksum isn't up to date in readme (#925)

* Fix #924: Checksum isn't up to date in readme

* Update README.md
Co-authored-by: Pablo Aguiar <scorphus@gmail.com>

README.md

@@ -44,7 +44,7 @@ fish install --path=~/.local/share/omf --config=~/.config/omf
 You can verify the integrity of the downloaded installer by verifying the script against [this checksum](bin/install.sha256):
 
 ```
-bb1f4025934600ea6feef2ec11660e17e2b6449c5a23c033860aed712ad328c9 install
+curl -sL https://raw.githubusercontent.com/oh-my-fish/oh-my-fish/master/bin/install.sha256 | shasum -a 256 --check
 ```
 
 You can also install Oh My Fish with Git or with an offline source tarball downloaded from the [releases page][releases]: