[mlir][nfc] Update Linalg matmul -> Vector OP test (#81416)

Updates "transform-op-matmul-to-outerproduct.mlir". Summary:
  * refines TD sequence so that it's easier to reason about the
     compilation pipeline (e.g.
     `transform.structured.vectorize_children_and_apply_patterns`
     is replaced with`transform.structured.vectorize `),
  * new input dims to be able to distinguish parallel from reduction
    dims,
  * updates LIT variable names (makes the output easier to follow),
  * removes "noise" from the expected LIT output (e.g. types).

These Linalg -> Vector tests using Transform Dialect are great reference
points for constructing lowering pipelines. This simplification +
clean-up will hopefully make it easier to follow.