[perl #49686] [CAGE] t/library/streams.t: Determine whether test can be divided into smaller files

Examination this file suggests that it is long because the tests are
largely data-driven.  Nonetheless, the file appears to be conceptually
whole.  Hence, there is no compelling case for subdividing this test
file.  I am closing the ticket.

• [perl #49686] [CAGE] t/library/streams.t: Determine whether test can be divided into smaller files by James Keenan via RT