[ArduinoJson] Update external library ArduinoJson.

Is needed to compile new ESP32 code.

lib/ArduinoJson/test/JsonArray/size.cpp

@@ -0,0 +1,35 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2018
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("JsonArray::size()") {
+  DynamicJsonBuffer _jsonBuffer;
+  JsonArray& _array = _jsonBuffer.createArray();
+
+  SECTION("increases after add()") {
+    _array.add("hello");
+    REQUIRE(1U == _array.size());
+
+    _array.add("world");
+    REQUIRE(2U == _array.size());
+  }
+
+  SECTION("remains the same after set()") {
+    _array.add("hello");
+    REQUIRE(1U == _array.size());
+
+    _array.set(0, "hello");
+    REQUIRE(1U == _array.size());
+  }
+
+  SECTION("remains the same after assigment") {
+    _array.add("hello");
+    REQUIRE(1U == _array.size());
+
+    _array[0] = "hello";
+    REQUIRE(1U == _array.size());
+  }
+}