Fix azure test (#902)

Summary:
Fix bug introduced by #849

- Replace `skipIfNoFSSpecS3` by `skipIfNoFSSpecAZ` for tests to access Azure Blob
- Add `adlfs` to conda test requirements.

Pull Request resolved: #902

Reviewed By: NivekT

Differential Revision: D41378561

Pulled By: ejguan

fbshipit-source-id: be99d1371379e1c87c2f2ac062b009f88575aa0a

test/requirements.yml

@@ -6,3 +6,4 @@ dependencies:
       - s3fs
       - numpy
       - datasets
+      - adlfs

test/test_remote_io.py

@@ -30,12 +30,26 @@
 
 try:
     import fsspec
+
+    HAS_FSSPEC = True
+except ImportError:
+    HAS_FSSPEC = False
+
+try:
     import s3fs
 
     HAS_FSSPEC_S3 = True
 except ImportError:
     HAS_FSSPEC_S3 = False
-skipIfNoFSSpecS3 = unittest.skipIf(not HAS_FSSPEC_S3, "no FSSpec with S3fs")
+skipIfNoFSSpecS3 = unittest.skipIf(not (HAS_FSSPEC and HAS_FSSPEC_S3), "no FSSpec with S3fs")
+
+try:
+    import adlfs
+
+    HAS_FSSPEC_AZ = True
+except ImportError:
+    HAS_FSSPEC_AZ = False
+skipIfNoFSSpecAZ = unittest.skipIf(not (HAS_FSSPEC and HAS_FSSPEC_AZ), "no FSSpec with adlfs")
 
 try:
     from torchdata._torchdata import S3Handler
@@ -213,7 +227,7 @@ def test_fsspec_io_iterdatapipe(self):
         res = list(fsspec_loader_dp)
         self.assertEqual(len(res), 18, f"{input} failed")
 
-    @skipIfNoFSSpecS3
+    @skipIfNoFSSpecAZ
     def test_fsspec_azure_blob(self):
         url = "public/curated/covid-19/ecdc_cases/latest/ecdc_cases.csv"
         account_name = "pandemicdatalake"