[XLA:GPU][NFC] Make GpuCompilerTest.CollectivePermuteDecompositionAndPipelining less brittle.
[XLA:GPU][NFC] Make GpuCompilerTest.CollectivePermuteDecompositionAndPipelining less brittle.

Previously, the test was relying on both

1. exact instruction names, and
2. explicit ordering of many pure and re-orderable HLO operations.

Both of these things can not be relied upon for testing, and this came up
as a blocker when trying to remove passes from the pipeline.

This change removes all the matches on exact instruction names and minimizes
the number of instructions that need to be explicitly ordered---while aiming
to preserve the spirit of the test.
