Added 1.11.3 FIPS to manifest (#73)

Author: deva26

site/manifest.json

@@ -22,6 +22,21 @@
         "https://istio.io/latest/news/releases/1.11.x/announcing-1.11.3/"
       ],
       "is_security_patch": false
+   },
+   {
+      "version": "1.11.3",
+      "flavor": "tetratefips",
+      "flavor_version": 0,
+      "k8s_versions": [
+        "1.17",
+        "1.18",
+        "1.19",
+        "1.20"
+      ],
+      "release_notes": [
+        "https://istio.io/latest/news/releases/1.11.x/announcing-1.11.3/"
+      ],
+      "is_security_patch": false
     },
     {
       "version": "1.11.3",