PR #10722: Consolidate Unit Tests for GEMM Rewriter
PR #10722: Consolidate Unit Tests for GEMM Rewriter

Imported from GitHub PR https://github.com/openxla/xla/pull/10722

Moves the unit tests in `xla/service/gpu/gemm_rewriter_test.cc` into `xla/service/gpu/tests/gemm_rewrite_test.cc`.
Copybara import of the project:

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e3056a172238a256214d856cf3ad5cb44099e06a by Philipp Hack <phack@nvidia.com>:

Merge GEMM rewriter unit tests.

Merging this change closes #10722

FUTURE_COPYBARA_INTEGRATE_REVIEW=https://github.com/openxla/xla/pull/10722 from philipphack:u_merged_gemm_test_xla e3056a172238a256214d856cf3ad5cb44099e06a
