[CI] Add tests for single precision batch transforms

[iamazeem]

Hi,

Currently, the tests for single precision batch transforms are missing.

Only these double precision tests are available:

regent-fft/test/fft_test.rg

Lines 431 to 433 in 3a966e3

	test_2d_double_to_complex64_batch_transform()
	test_2d_complex64_to_complex64_batch_transform()
	test_3d_complex64_to_complex64_batch_transform()

For the sake of completion, these tests may be added.
Similarly, other missing tests (for precision and dimensions) may also be added if need be.

Regards!

CC: @arjunkunna