fix another corner case for sembr tool

.github/workflows/ci.yml

@@ -87,4 +87,4 @@ jobs:
         continue-on-error: true
         run: |
           # using split_inclusive that uses regex feature that uses an unstable feature
-          RUSTC_BOOTSTRAP=true cargo run --manifest-path ci/sembr/Cargo.toml src
+          RUSTC_BOOTSTRAP=1 cargo run --manifest-path ci/sembr/Cargo.toml src

ci/sembr/src/main.rs

@@ -22,6 +22,8 @@ struct Cli {
 static REGEX_IGNORE: LazyLock<Regex> =
     LazyLock::new(|| Regex::new(r"^\s*(\d\.|\-|\*)\s+").unwrap());
 static REGEX_IGNORE_END: LazyLock<Regex> = LazyLock::new(|| Regex::new(r"(\.|\?|;|!)$").unwrap());
+static REGEX_IGNORE_LINK_TARGETS: LazyLock<Regex> =
+    LazyLock::new(|| Regex::new(r"^\[.+\]: ").unwrap());
 static REGEX_SPLIT: LazyLock<Regex> = LazyLock::new(|| Regex::new(r"(\.|\?|;|!)\s+").unwrap());
 
 fn main() -> Result<()> {
@@ -94,6 +96,7 @@ fn ignore(line: &str, in_code_block: bool) -> bool {
         || line.starts_with('#')
         || line.trim().is_empty()
         || REGEX_IGNORE.is_match(line)
+        || REGEX_IGNORE_LINK_TARGETS.is_match(line)
 }
 
 fn comply(content: &str) -> String {
@@ -221,6 +224,15 @@ fn test_prettify_prefix_spaces() {
     assert_eq!(expected, lengthen_lines(original, 50));
 }
 
+#[test]
+fn test_prettify_ignore_link_targets() {
+    let original = "\
+[a target]: https://example.com
+[another target]: https://example.com
+";
+    assert_eq!(original, lengthen_lines(original, 100));
+}
+
 #[test]
 fn test_sembr_then_prettify() {
     let original = "\