Fix FITS tests with python3.7, reduce memory usage in rand aug tests (#4844)

* Fix FITS tests with python3.7
* Reduce memory consumption in rand aug tests
---------

Signed-off-by: Kamil Tokarski <[email protected]>

Author: stiepan

dali/test/python/auto_aug/test_rand_augment.py

@@ -36,9 +36,10 @@
         itertools.product(("cpu", "gpu"), (True, False), (True, False), (None, 0), (True, False)))))
 def test_run_rand_aug(i, args):
     dev, uniformly_resized, use_shape, fill_value, specify_translation_bounds = args
-    batch_sizes = [1, 8, 7, 64, 13, 64, 128]
-    ns = [1, 2, 3, 4]
-    ms = [0, 15, 30]
+    # Keep batch_sizes ns and ms length co-prime
+    batch_sizes = [1, 8, 7, 13, 31, 64, 128]
+    ns = [1, 2, 3]
+    ms = [0, 12, 15, 30]
     batch_size = batch_sizes[i % len(batch_sizes)]
     n = ns[i % len(ns)]
     m = ms[i % len(ms)]

dali/test/python/reader/test_fits.py

@@ -60,7 +60,7 @@ def get_astropy_dtypes(compression):
     # The astropy is not actively developed for Python3.6 and the last available
     # version does not support some dtypes
     vi = sys.version_info
-    if vi.major < 3 or (vi.major == 3 and vi.minor <= 6):
+    if vi.major < 3 or (vi.major == 3 and vi.minor <= 7):
         excluded |= {np.int8}
     # Astropy doesn't support writing those types to compressed image
     if compression: