Merge branch 'patch-2' into 'master'

Update osx.md so the update instructions work as well as the install instructions

See merge request gitlab-org/gitlab-runner!1402

docs/install/osx.md

@@ -101,7 +101,7 @@ executing the `install` command, by checking the
 1. Download the binary to replace the Runner's executable:
 
     ```bash
-    curl -o /usr/local/bin/gitlab-runner https://gitlab-runner-downloads.s3.amazonaws.com/latest/binaries/gitlab-runner-darwin-amd64
+    sudo curl -o /usr/local/bin/gitlab-runner https://gitlab-runner-downloads.s3.amazonaws.com/latest/binaries/gitlab-runner-darwin-amd64
     ```
 
     You can download a binary for every available version as described in
@@ -110,7 +110,7 @@ executing the `install` command, by checking the
 1. Give it permissions to execute:
 
     ```bash
-    chmod +x /usr/local/bin/gitlab-runner
+    sudo chmod +x /usr/local/bin/gitlab-runner
     ```
 
 1. Start the service: