Fix square corners on line numbers when code is collapsed

Author: GuillaumeGomez

Diff for: src/librustdoc/html/static/css/rustdoc.css

@@ -746,7 +746,8 @@ ul.block, .block li {
 }
 
 .rustdoc .example-wrap > pre,
-.rustdoc .scraped-example .src-line-numbers {
+.rustdoc .scraped-example .src-line-numbers,
+.rustdoc .scraped-example .src-line-numbers > pre {
 	border-radius: 6px;
 }
 
@@ -755,7 +756,8 @@ If the code example line numbers are displayed, there will be a weird radius in
 both the code example and the line numbers, so we need to remove the radius in this case.
 */
 .rustdoc .example-wrap > .example-line-numbers,
-.rustdoc .scraped-example .src-line-numbers {
+.rustdoc .scraped-example .src-line-numbers,
+.rustdoc .scraped-example .src-line-numbers > pre {
 	border-top-right-radius: 0;
 	border-bottom-right-radius: 0;
 }

Diff for: tests/rustdoc-gui/docblock-code-block-line-number.goml

@@ -108,6 +108,17 @@ assert-local-storage: {"rustdoc-line-numbers": "true" }
 // Same check with scraped examples line numbers.
 go-to: "file://" + |DOC_PATH| + "/scrape_examples/fn.test_many.html"
 
+assert-css: (
+    ".scraped-example .src-line-numbers > pre",
+    {
+        // There should not be a radius on the right of the line numbers.
+        "border-top-left-radius": "6px",
+        "border-bottom-left-radius": "6px",
+        "border-top-right-radius": "0px",
+        "border-bottom-right-radius": "0px",
+    },
+    ALL,
+)
 assert-css: (
     ".scraped-example .src-line-numbers",
     {