update the version of nlohmann/json in requirements.txt (#107)

* update the version of json in requirements.txt

* removed C++ 17 requirement
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 4946f09..c7b0e99 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -13,7 +13,7 @@
 
 set(INJA_INSTALL_INCLUDE_DIR "include")
 
-set(CMAKE_CXX_STANDARD 17)
+# set(CMAKE_CXX_STANDARD 17)
 set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} ${PROJECT_SOURCE_DIR}/cmake)
 set(CMAKE_BUILD_TYPE Debug)
 # set(CMAKE_BUILD_TYPE Release)
@@ -36,7 +36,7 @@
   $<INSTALL_INTERFACE:${INJA_INSTALL_INCLUDE_DIR}>
 )
 
-target_compile_features(inja INTERFACE cxx_std_11)
+# target_compile_features(inja INTERFACE cxx_std_11)
 
 set(INJA_PACKAGE_USE_EMBEDDED_JSON OFF)
 
diff --git a/requirements.txt b/requirements.txt
index e42faaa..fd4c518 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1 +1 @@
-nlohmann/json@v3.5.0
+nlohmann/json@v3.6.1