Move more pass from Flow stage to GlobalOptimization stage. (#14707)

- Move four more passes to GlobalOptimization stage.
  - ConvertElementwiseToLinalgPass
  - GeneralizeLinalgNamedOpsPass
  - FuseDequantizationMatmulPass
  - FoldUnitExtentDimsPass
 - Move Flow transformation_pipeline.mlir test to GlobalOptimization/test. It is mainly for testing ConvertElementwiseToLinalg pass which is also tested upstream. We probably can remove it as a follow-up.
diff --git a/tools/test/compile_pipelines.mlir b/tools/test/compile_pipelines.mlir
index 7275ec9..2fd4a6c 100644
--- a/tools/test/compile_pipelines.mlir
+++ b/tools/test/compile_pipelines.mlir
@@ -1,6 +1,7 @@
 // RUN: iree-opt --iree-common-input-transformation-pipeline %s | \
 // RUN: iree-opt --iree-abi-transformation-pipeline - | \
 // RUN: iree-opt --iree-common-input-transformation-pipeline - | \
+// RUN: iree-opt --iree-global-optimization-transformation-pipeline - | \
 // RUN: iree-opt --iree-flow-transformation-pipeline - | \
 // RUN: iree-opt --iree-stream-transformation-pipeline - | \
 // RUN: iree-opt --iree-hal-transformation-pipeline --iree-hal-target-backends=vmvx - | \