Added CMAKE_PREFIX_PATH to json recipe.

recipes/json/recipe.py

@@ -1,5 +1,6 @@
 
 
+import os
 import re
 from SCons.Script import *
 
@@ -8,7 +9,8 @@ def _git_cook(env: Environment, repo: dict) -> dict:
     checkout_root = repo['checkout_root']
     build_result = env.CMakeProject(project_root=checkout_root)
     return {
-        'CPPPATH': build_result['CPPPATH']
+        'CPPPATH': build_result['CPPPATH'],
+        'CMAKE_PREFIX_PATH': [build_result['install_dir']]
     }