Adding google/cel-cpp maintainers. (#6506)

Adding maintainers from the CEL Team.

Author: jnthntatum

modules/cel-cpp/metadata.json

@@ -6,6 +6,24 @@
             "github": "ferstlf",
             "github_user_id": 64520639,
             "name": "Florian Ferstl"
+        },
+        {
+            "email": "[email protected]",
+            "github": "cel-expr",
+            "github_user_id": 186625994,
+            "name": "CEL Team"
+        },
+        {
+            "github": "jnthntatum",
+            "github_user_id": 733856
+        },
+        {
+            "github": "jcking",
+            "github_user_id": 997958
+        },
+        {
+            "github": "tristonianjones",
+            "github_user_id": 483300
         }
     ],
     "repository": [
@@ -17,4 +35,4 @@
         "0.13.0"
     ],
     "yanked_versions": {}
-}
+}