[develop2] add build_modules to provided deprecated warning (#12578)

* [develop2] add `build_modules` to mock property info

* fix copy paste

* Update test_legacy_cpp_info.py

* add missing test

Co-authored-by: James <james@conan.io>

conans/model/build_info.py

@@ -89,6 +89,7 @@ def __init__(self, set_defaults=False):
         # LEGACY 1.X fields, can be removed in 2.X
         self.names = MockInfoProperty("cpp_info.names")
         self.filenames = MockInfoProperty("cpp_info.filenames")
+        self.build_modules = MockInfoProperty("cpp_info.build_modules")
 
         if set_defaults:
             self.includedirs = ["include"]

conans/test/integration/conan_v2/test_legacy_cpp_info.py

@@ -13,11 +13,15 @@ class Pkg(ConanFile):
             def package_info(self):
                 self.cpp_info.components["comp"].names["cmake_find_package"] = "hello"
                 self.cpp_info.components["comp"].names["cmake_find_package_multi"] = "hello"
+                self.cpp_info.components["comp"].build_modules["cmake_find_package"] = ["nice_rel_path"]
+                self.cpp_info.components["comp"].build_modules["cmake_find_package_multi"] = ["nice_rel_path"]
 
                 self.cpp_info.names["cmake_find_package"] = "absl"
                 self.cpp_info.names["cmake_find_package_multi"] = "absl"
                 self.cpp_info.filenames["cmake_find_package"] = "tensorflowlite"
                 self.cpp_info.filenames["cmake_find_package_multi"] = "tensorflowlite"
+                self.cpp_info.build_modules["cmake_find_package"] = ["nice_rel_path"]
+                self.cpp_info.build_modules["cmake_find_package_multi"] = ["nice_rel_path"]
 
                 self.env_info.whatever = "whatever-env_info"
                 self.user_info.whatever = "whatever-user_info"
@@ -28,5 +32,5 @@ def package_info(self):
               "Conan 2.X. Please, update your recipes unless you are maintaining compatibility " \
               "with Conan 1.X"
 
-    for name in ["cpp_info.names", "cpp_info.filenames", "env_info", "user_info"]:
+    for name in ["cpp_info.names", "cpp_info.filenames", "env_info", "user_info", "cpp_info.build_modules"]:
         assert message.format(name) in c.out