message: Fix deps/json submodule name to match location
diff: [submodule "deps/mctrl"]
  path = deps/mctrl
  url = https://github.com/mity/mctrl.git
  -[submodule "src/json"]
  +[submodule "deps/json"]
  path = deps/json
  url = https://github.com/nlohmann/json.git
  [submodule "deps/pugixml"]
  