Fix typo in config.example.toml comments (to -> or)

[ssmendon]

Standards checklist:

I have not tested this change in any way.

• [x] The PR title is descriptive.
• [ ] The code compiles (cargo build)
• [ ] The code passes rustfmt (cargo fmt)
• [ ] The code passes clippy (cargo clippy)
• [ ] The code passes tests (cargo test)
• [ ] Optional: I have tested the code myself
  • [ ] I also tested that Topgrade skips the step where needed

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