Remove some useless log

Some log wouldn't be helpful for users, like: ``` [2025-01-27T11:43:26Z ERROR live_server::file_layer::watcher] SendError(()) ``` And another example is when `--index` is enabled, there is still such warning message: ``` [2025-01-27T11:41:43Z WARN live_server::http_layer::server] Failed to read "/Users/mirus/Projects/github/live-server/index.html": No such file or directory (os error 2) [2025-01-27T11:41:43Z WARN live_server::http_layer::server] Failed to read "/Users/mirus/Projects/github/live-server/index.html": No such file or directory (os error 2) [2025-01-27T11:41:43Z WARN live_server::http_layer::server] Failed to read "/Users/mirus/Projects/github/live-server/index.html": No such file or directory (os error 2) [2025-01-27T11:41:43Z WARN live_server::http_layer::server] Failed to read "/Users/mirus/Projects/github/live-server/index.html": No such file or directory (os error 2) [2025-01-27T11:41:43Z WARN live_server::http_layer::server] Failed to read "/Users/mirus/Projects/github/live-server/index.html": No such file or directory (os error 2) [2025-01-27T11:41:43Z WARN live_server::http_layer::server] Failed to read "/Users/mirus/Projects/github/live-server/index.html": No such file or directory (os error 2) [2025-01-27T11:41:43Z WARN live_server::http_layer::server] Failed to read "/Users/mirus/Projects/github/live-server/index.html": No such file or directory (os error 2) [2025-01-27T11:42:22Z WARN live_server::http_layer::server] Failed to read "/Users/mirus/Projects/github/live-server/index.html": No such file or directory (os error 2) [2025-01-27T11:42:23Z WARN live_server::http_layer::server] Failed to read "/Users/mirus/Projects/github/live-server/index.html": No such file or directory (os error 2) [2025-01-27T11:42:23Z WARN live_server::http_layer::server] Failed to read "/Users/mirus/Projects/github/live-server/index.html": No such file or directory (os error 2) [2025-01-27T11:42:23Z WARN live_server::http_layer::server] Failed to read "/Users/mirus/Projects/github/live-server/index.html": No such file or directory (os error 2) [2025-01-27T11:42:23Z WARN live_server::http_layer::server] Failed to read "/Users/mirus/Projects/github/live-server/index.html": No such file or directory (os error 2) [2025-01-27T11:42:23Z WARN live_server::http_layer::server] Failed to read "/Users/mirus/Projects/github/live-server/index.html": No such file or directory (os error 2) [2025-01-27T11:42:24Z WARN live_server::http_layer::server] Failed to read "/Users/mirus/Projects/github/live-server/index.html": No such file or directory (os error 2) ``` Such messages should be removed.