Update ClusterInstructionsModal.tsx

Fix Regex for downloading porter CLI to be in sync with the rest of the docs.

dashboard/src/main/home/modals/ClusterInstructionsModal.tsx

@@ -34,7 +34,7 @@ export default class ClusterInstructionsModal extends Component<
               <br />
               name=$(curl -s
               https://api.github.com/repos/porter-dev/porter/releases/latest |
-              grep "browser_download_url.*porter_.*_Darwin_x86_64\.zip" | cut -d
+              grep "browser_download_url.*/porter_.*_Darwin_x86_64\.zip" | cut -d
               ":" -f 2,3 | tr -d \")
               <br />
               name=$(basename $name)