Fix index.bs markup

QueenieZqq · web-flow · commit cba99261c960 · 2025-02-27T12:40:56.000-08:00
diff --git a/index.bs b/index.bs
@@ -16,4 +16,4 @@ Die On: warning
 Introduction {#intro}
 =====================
 
-For now, see the [explainer]([REPOSITORYURL]).
+For now, see the [explainer](https://github.com/explainers-by-googlers/proofreader-api).
