codebase.md: fix minor markdown typo

PiperOrigin-RevId: 585043683
Change-Id: Ia064ccb13df0e4aa96398e495beb9353a3950677

site/en/contribute/codebase.md

diff --git a/site/en/contribute/codebase.md b/site/en/contribute/codebase.md
index 3189a5b..9bb908a 100644
--- a/site/en/contribute/codebase.md
+++ b/site/en/contribute/codebase.md
@@ -1563,7 +1563,7 @@
 
 ## JNI bits {:#jni-bits}
 
-The server of Bazel is_ mostly _written in Java. The exception is the parts that
+The server of Bazel is _mostly_ written in Java. The exception is the parts that
 Java cannot do by itself or couldn't do by itself when we implemented it. This
 is mostly limited to interaction with the file system, process control and
 various other low-level things.