Bazel DevSite: Add link to 5.2 docs

PiperOrigin-RevId: 453688470
Change-Id: I70c20621b6e5b5e1d15de4a0beb1ad79c8259572
diff --git a/site/en/versions/_toc.yaml b/site/en/versions/_toc.yaml
index 86b8114..7bc5725 100644
--- a/site/en/versions/_toc.yaml
+++ b/site/en/versions/_toc.yaml
@@ -1,4 +1,6 @@
 toc:
+- label: "5.2 ↗"
+  path: https://docs.bazel.build/versions/5.2.0/bazel-overview.html
 - label: "5.1.1 ↗"
   path: https://docs.bazel.build/versions/5.1.1/bazel-overview.html
 - label: "5.1 ↗"