Fix for broken links on bazel.build - updated the .md headers for these three files

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PiperOrigin-RevId: 151319959
MOS_MIGRATED_REVID=151319959
diff --git a/site/versions/master/docs/install-ubuntu.md b/site/versions/master/docs/install-ubuntu.md
index 3fe9ee3..cdc88f7 100644
--- a/site/versions/master/docs/install-ubuntu.md
+++ b/site/versions/master/docs/install-ubuntu.md
@@ -1,8 +1,7 @@
---------------------------------------------------------------------------------
-
+---
 layout: documentation
-
-## title: Installing Bazel on Ubuntu
+title: Installing Bazel on Ubuntu
+---
 
 # <a name="ubuntu"></a>Install Bazel on Ubuntu