error: looks like a footnote ref, but has no matching footnote
  --> tests/ui/doc_suspicious_footnotes_include.txt:1:23
   |
LL | This is not a footnote[^1].
   |                       ^^^^
   |
   = note: `-D clippy::doc-suspicious-footnotes` implied by `-D warnings`
   = help: to override `-D warnings` add `#[allow(clippy::doc_suspicious_footnotes)]`
help: add footnote definition
   |
LL ~ [^2]: hello world
LL + 
LL + [^1]: <!-- description -->
   |

error: aborting due to 1 previous error