Refactor refresh_author_db function to set custom cache directory using current working directory

BridgeMentor/utils.py

@@ -18,7 +18,6 @@ def refresh_author_db(check_time=False):
             cache_dir=custom_cache_dir
         )
         print(f"Downloaded to: {file_path}")
-        destination_path = os.path.join(os.getcwd(), "db.sqlite3")
-        shutil.copy(file_path, destination_path)
+        shutil.copy(file_path, db_file)
         print(
-            f"db.sqlite3 Copied to current directory: {destination_path}")
+            f"db.sqlite3 Copied to current directory: {db_file}")