workaround new_task_join_error depends on tokio rt

Signed-off-by: tison <[email protected]>

core/src/raw/tokio_util.rs

@@ -15,9 +15,10 @@
 // specific language governing permissions and limitations
 // under the License.
 
-use crate::*;
+use crate::{Error, ErrorKind};
 
 /// Parse tokio error into opendal::Error.
-pub fn new_task_join_error(e: tokio::task::JoinError) -> Error {
+// HACK - tokio::task::JoinError is not always present, use an existential type.
+pub fn new_task_join_error(e: impl Into<anyhow::Error>) -> Error {
     Error::new(ErrorKind::Unexpected, "tokio task join failed").set_source(e)
 }