Writing to ozone failed without setting alluxio.underfs.version

[Haoning-Sun]

Alluxio Version:
2.x

Describe the bug
Writing to ozone failed without setting alluxio.underfs.version.

WARN  ExtensionFactoryRegistry - No factory implementation supports the path o3fs://xxx.xxx/
WARN  UnderFileSystemFactoryRegistry - Versions [xxx] are supported for path o3fs://xxx.xxx/ but you have configured version: xxx

java.lang.IllegalArgumentException: No Under File System Factory found for: o3fs://xxx.xxx/
        at alluxio.underfs.UnderFileSystem$Factory.create(UnderFileSystem.java:95)
        at alluxio.underfs.AbstractUfsManager.getOrAdd(AbstractUfsManager.java:132)
        at alluxio.underfs.AbstractUfsManager.lambda$addMount$0(AbstractUfsManager.java:183)
        at alluxio.underfs.UfsManager$UfsClient.acquireUfsResource(UfsManager.java:61)
        at alluxio.worker.grpc.UfsFileWriteHandler.createUfsFile(UfsFileWriteHandler.java:155)
        at alluxio.worker.grpc.UfsFileWriteHandler.writeBuf(UfsFileWriteHandler.java:139)
        at alluxio.worker.grpc.UfsFileWriteHandler.writeBuf(UfsFileWriteHandler.java:49)
        at alluxio.worker.grpc.AbstractWriteHandler.writeData(AbstractWriteHandler.java:281)
        at alluxio.worker.grpc.AbstractWriteHandler.lambda$writeDataMessage$1(AbstractWriteHandler.java:179)
        at io.grpc.internal.SerializingExecutor.run(SerializingExecutor.java:123)
        at alluxio.worker.grpc.GrpcExecutors$ImpersonateThreadPoolExecutor.lambda$execute$0(GrpcExecutors.java:159)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
        at java.lang.Thread.run(Thread.java:748)

To Reproduce

1. Start a cluster without setting alluxio.underfs.version;
2. Add a mount point for an ozone bucket without setting alluxio.underfs.version;
3. Upload a file to the ozone bucket.

Expected behavior
Can write files.

Are you planning to fix it
Yes.

[jja725]

Thanks for raising the issue and fix it! I would take a look