PyAPI: don't use deprecated PyModule_GetFilename

Allows compiling with newer Python versions.
Also add missing decref when compiling as a py-module.

source/blender/python/generic/bpy_internal_import.c

@@ -248,8 +248,17 @@ PyObject *bpy_text_reimport(PyObject *module, int *found)
 	if ((name = PyModule_GetName(module)) == NULL)
 		return NULL;
 
-	if ((filepath = (char *)PyModule_GetFilename(module)) == NULL)
+	{
-		return NULL;
+		PyObject *module_file = PyModule_GetFilenameObject(module);
+		if (module_file == NULL) {
+			return NULL;
+		}
+		filepath = (char *)_PyUnicode_AsString(module_file);
+		Py_DECREF(module_file);
+		if (filepath == NULL) {
+			return NULL;
+		}
+	}
 
 	/* look up the text object */
 	text = BLI_findstring(&maggie->text, BLI_path_basename(filepath), offsetof(ID, name) + 2);

source/blender/python/generic/py_capi_utils.c

@@ -300,7 +300,14 @@ void PyC_FileAndNum(const char **filename, int *lineno)
 		if (mod_name) {
 			PyObject *mod = PyDict_GetItem(PyImport_GetModuleDict(), mod_name);
 			if (mod) {
-				*filename = PyModule_GetFilename(mod);
+				PyObject *mod_file = PyModule_GetFilenameObject(mod);
+				if (mod_file) {
+					*filename = _PyUnicode_AsString(mod_name);
+					Py_DECREF(mod_file);
+				}
+				else {
+					PyErr_Clear();
+				}
 			}
 
 			/* unlikely, fallback */

source/blender/python/intern/bpy_interface.c

@@ -869,6 +869,7 @@ static void bpy_module_delay_init(PyObject *bpy_proxy)
 
 	BLI_strncpy(filename_abs, filename_rel, sizeof(filename_abs));
 	BLI_path_cwd(filename_abs, sizeof(filename_abs));
+	Py_DECREF(filename_obj);
 
 	argv[0] = filename_abs;
 	argv[1] = NULL;