Auto merge of #18924 - mbrubeck:doc, r=Manishearth

Fix commonmark Markdown warnings in docs, part 1

Fixes warnings from rust-lang/rust#44229 when `--enable-commonmark` is passed to rustdoc.

This is mostly a global find-and-replace for bare URIs on lines by themselves in doc comments.

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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes do not require tests because they are doc formatting changes only

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1 files changed, 1 insertions, 1 deletions

diff --git a/components/layout/flex.rs b/components/layout/flex.rs
index 6d969ef8643..929b4cb1838 100644
--- a/components/layout/flex.rs
+++ b/components/layout/flex.rs
@@ -264,7 +264,7 @@ impl FlexLine {
     /// This method implements the flexible lengths resolving algorithm.
     /// The 'collapse' parameter is used to indicate whether items with 'visibility: collapse'
     /// is included in length resolving. The result main size is stored in 'item.main_size'.
-    /// https://drafts.csswg.org/css-flexbox/#resolve-flexible-lengths
+    /// <https://drafts.csswg.org/css-flexbox/#resolve-flexible-lengths>
     pub fn flex_resolve(&mut self, items: &mut [FlexItem], collapse: bool) {
         let mut total_grow = 0.0;
         let mut total_shrink = 0.0;