[mlir][func] Add support for nested tuples to TestDecomposeCallGraphTypes.

Nested tuples were only supported in some narrow edge cases (and
potentially only because the test ops like `test.make_tuple` aren't
properly verified). This patch adds a couple of test cases with tested
tuple types and makes them work in the test pass by extending the
argument materialization and decomposition functions.

Reviewed By: silvas

Differential Revision: https://reviews.llvm.org/D143579