[chore] move minirtc into submodules

.gitmodules

@@ -1,3 +1,3 @@
-[submodule "thirdparty/minirtc"]
-	path = thirdparty/minirtc
+[submodule "submodules/minirtc"]
+	path = submodules/minirtc
 	url = https://github.com/kunkundi/minirtc.git

xmake.lua

@@ -46,7 +46,7 @@ end
 
 add_packages("spdlog", "imgui")
 
-includes("thirdparty")
+includes("submodules")
 
 target("rd_log")
     set_kind("object")