Add the following SWANGLE test failure to
deqp_gles31_test_expectations.txt:

dEQP-GLES31.functional.debug.negative_coverage.get_error.buffer.framebuffer_texture2d

Bug: angleproject:3590
Test: None
Change-Id: I0f234ea2d7a90e2b95220b152cb0da3822df1ef3
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/1933764Reviewed-by: Courtney Goeltzenleuchter <courtneygo@google.com>
Reviewed-by: Tobin Ehlis <tobine@google.com>
Commit-Queue: Tim Van Patten <timvp@google.com>