convert_script_files does not require script to exist

fixes <python-poetry/poetry#8856>

src/poetry/core/masonry/builders/builder.py

@@ -364,16 +364,6 @@ def convert_script_files(self) -> list[Path]:
 
                 abs_path = Path.joinpath(self._path, source)
 
-                if not abs_path.exists():
-                    raise RuntimeError(
-                        f"{abs_path} in script specification ({name}) is not found."
-                    )
-
-                if not abs_path.is_file():
-                    raise RuntimeError(
-                        f"{abs_path} in script specification ({name}) is not a file."
-                    )
-
                 script_files.append(abs_path)
 
         return script_files

tests/masonry/builders/test_builder.py

@@ -190,19 +190,6 @@ def test_metadata_with_url_dependencies() -> None:
     )
 
 
-def test_missing_script_files_throws_error() -> None:
-    builder = Builder(
-        Factory().create_poetry(
-            Path(__file__).parent / "fixtures" / "script_reference_file_missing"
-        )
-    )
-
-    with pytest.raises(RuntimeError) as err:
-        builder.convert_script_files()
-
-    assert "is not found." in str(err.value)
-
-
 def test_invalid_script_files_definition() -> None:
     with pytest.raises(RuntimeError) as err:
         Builder(