Disallow /tool_runner? in robots.txt

[dannon]

This was getting spammed on main causing lots of extraneous jobs. Might need to follow up with updates to the tool panel to use direct tool links like: https://usegalaxy.org/root?tool_id=toolshed.g2.bx.psu.edu/repos/iuc/datamash_ops/datamash_ops/1.8+galaxy0

Any other problematic spammed routes or things we otherwise don't want crawled that folks can think of?

How to test the changes?

(Select all options that apply)

• I've included appropriate automated tests.
• This is a refactoring of components with existing test coverage.
• Instructions for manual testing are as follows:
  1. [add testing steps and prerequisites here if you didn't write automated tests covering all your changes]

License

• I agree to license these and all my past contributions to the core galaxy codebase under the MIT license.

[github-actions]

This PR was merged without a "kind/" label, please correct.

[natefoo]

I was just checking... the ? is probably unnecessary but with some testing it looks like it probably does cover what we want it to cover (not a bare /tool_runner with no args, but that's fine).