Update numpy dependency to 1.22.0.

GH advisory on versions < 1.22.0 https://github.com/advisories/GHSA-fpfv-jqm9-f5jm.

PiperOrigin-RevId: 518601694
diff --git a/python/requirements.txt b/python/requirements.txt
index 2364158..ee6dfb4 100644
--- a/python/requirements.txt
+++ b/python/requirements.txt
@@ -1 +1 @@
-numpy==1.22.0
+numpy==1.21.6