refactor: respect data_home as root data home directory (#6050)

* refactor: initialize logging dir by using data_home

* chore: remove tail '/' for dir name

src/store-api/src/path_utils.rs

@@ -18,7 +18,7 @@
 use crate::storage::{RegionId, RegionNumber, TableId};
 
 /// WAL dir for local file storage
-pub const WAL_DIR: &str = "wal/";
+pub const WAL_DIR: &str = "wal";
 
 /// Data dir for table engines
 pub const DATA_DIR: &str = "data/";