json-for-modern-cpp: bump to v3.1.0

Signed-off-by: Adam Duskett <aduskett@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

package/json-for-modern-cpp/json-for-modern-cpp.hash

@@ -1,3 +1,3 @@
 # Locally computed
-sha256	402464cd6d50c81bb6a683d07c537e5a8c4684fd1186826d3aa1385ce6adac13	json-v3.0.1.tar.gz
+sha256	b20be343922f73504baf8a01543c2a42d16e01f18bb231b324a8959416ccf4f8	json-v3.1.0.tar.gz
 sha256	6a6115fc4a7239a135f2dce8d33f94cb8a936b8f608ac0f6699fbac278b0dd5b	LICENSE.MIT

package/json-for-modern-cpp/json-for-modern-cpp.mk

@@ -4,7 +4,7 @@
 #
 ################################################################################
 
-JSON_FOR_MODERN_CPP_VERSION = v3.0.1
+JSON_FOR_MODERN_CPP_VERSION = v3.1.0
 JSON_FOR_MODERN_CPP_SOURCE = json-${JSON_FOR_MODERN_CPP_VERSION}.tar.gz
 JSON_FOR_MODERN_CPP_SITE = $(call github,nlohmann,json,$(JSON_FOR_MODERN_CPP_VERSION))
 JSON_FOR_MODERN_CPP_LICENSE = MIT