Update .bazelversion to 6.2.1

Change-Id: I50083f14e6b6a889880775ae9953df9152e528b5
diff --git a/.bazelversion b/.bazelversion
index ac14c3d..024b066 100644
--- a/.bazelversion
+++ b/.bazelversion
@@ -1 +1 @@
-5.1.1
+6.2.1