Fix Pipeline syntax in `fileExists` examples

[MarkEWaite]

Fix Pipeline syntax errors in fileExists examples

Reported in documentation feedback sheet

• [x] Make sure you are opening from a topic/feature/bugfix branch (right side) and not your main branch!
• [x] Ensure that the pull request title represents the desired changelog entry
• [x] Please describe what you did
• [x] Link to relevant issues in GitHub or Jira
• [x] Link to relevant pull requests, esp. upstream and downstream changes
• ~~Ensure you have provided tests - that demonstrates feature works or fixes the issue~~

[Bananeweizen]

👍🏻 Can somebody with the necessary powers please merge this one? I was just going to raise a second PR to fix the "rersources" typos. :)