Change how Bitbucket auth variables are shown

content/docs/self-hosted-runners.md

@@ -367,7 +367,7 @@ In either case, the steps to create a `REPO_TOKEN` are:
 
 1. Use a Base64 encoder of your choice to encode a Bitbucket username and
    password:
-   - `echo -n $USERNAME:$PASSWORD | base64`. The `-n` ensures the base64 does
+   - `echo -n {Bitbucket username}:{app password} | base64`. The `-n` ensures the base64 does
      not contain the trailing newline that `echo` adds by default.
    - copy the resulting Base64 token
 2. In your repository, go to **Repository Settings** → **Repository