Fix link for the internal version of the doc.

PiperOrigin-RevId: 410441591
diff --git a/src/main/java/com/google/devtools/build/docgen/templates/be/make-variables.vm b/src/main/java/com/google/devtools/build/docgen/templates/be/make-variables.vm
index 96f3cfa..33745c0 100644
--- a/src/main/java/com/google/devtools/build/docgen/templates/be/make-variables.vm
+++ b/src/main/java/com/google/devtools/build/docgen/templates/be/make-variables.vm
@@ -440,8 +440,8 @@
 
 <p>
   Rule and <a href="../toolchains.html">toolchain</a> writers can define
-  completely custom variables by returning a <a
-  href="../skylark/lib/TemplateVariableInfo.html">TemplateVariableInfo</a>
+  completely custom variables by returning a
+  <a href="../skylark/lib/TemplateVariableInfo.html">TemplateVariableInfo</a>
   provider. Any rules depending on these through the
   <code>toolchains</code> attribute can then read their values:
 </p>