Keep consistent formatting

CMakeLists.txt

@@ -160,7 +160,7 @@ if(JSON_Install)
             FILES ${NLOHMANN_NATVIS_FILE}
             DESTINATION .
     )
-endif()
+    endif() # NLOHMANN_ADD_NATVIS
     export(
         TARGETS ${NLOHMANN_JSON_TARGET_NAME}
         NAMESPACE ${PROJECT_NAME}::
@@ -180,4 +180,4 @@ endif()
         FILES "${CMAKE_CURRENT_BINARY_DIR}/${PROJECT_NAME}.pc"
         DESTINATION ${NLOHMANN_JSON_PKGCONFIG_INSTALL_DIR}
     )
-endif()
+endif() # JSON_Install