fix(ens): remove abi_ens_resolver v8 backwards-compat NameNotFound catch

[genisis0x]

What

Closes #3580.

web3/_utils/normalizers.py:227 had a TODO flagging the try/except NameNotFound block for removal in v8:

try:
    return type_str, validate_name_has_address(_ens, val)
except NameNotFound as e:
    # TODO: This try/except is to keep backwards compatibility when we
    #  removed the mainnet requirement. Remove this in web3.py v8 and allow
    #  NameNotFound to raise.
    if not isinstance(_ens, StaticENS):
        raise InvalidAddress(f"{e}")
    raise e

v8 has shipped (8.0.0-beta.3), so the backward-compat wrap can go.

Changes

• web3/_utils/normalizers.py: drop the try/except and let NameNotFound propagate from validate_name_has_address directly. The sync resolver now matches async_abi_ens_resolver (line 282-304), which already has no such guard — closing a sync/async inconsistency the TODO already implied.
• web3/_utils/normalizers.py: remove the now-unused StaticENS and NameNotFound imports.
• tests/core/middleware/test_name_to_address_middleware.py::test_fail_name_resolver: switch the expectation from InvalidAddress to NameNotFound. The async counterpart at line 179 (test_async_fail_name_resolver) already expects NameNotFound, so this aligns the two paths.
• newsfragments/3580.breaking.rst: user-facing breaking-change note.

Compat surface

The only callers exposed to the change are those that previously caught InvalidAddress on ENS lookup failures specifically. Two filtered grep sweeps to confirm no internal callers in the repo depend on the old shape:

• All other pytest.raises(InvalidAddress) sites in tests/core/contracts/test_contract_call_interface.py and tests/core/utilities/test_validation.py pass non-checksum hex addresses through validate_address, not ENS names through abi_ens_resolver, so they keep raising InvalidAddress as before.
• Async-side tests that exercise the same surface already expect NameNotFound.

Tests

$ python -m pytest tests/core/middleware/test_name_to_address_middleware.py tests/core/contracts/test_contract_call_interface.py -q
423 passed, 7 xfailed in 22.60s

$ python -m pytest tests/core/ -q
13088 passed, 7 skipped, 9 xfailed in 237s
(one pre-existing macOS-only failure in tests/core/providers/test_auto_provider.py::test_get_dev_ipc_path
 unrelated to this change — Python's tempfile.gettempdir() resolves /tmp to /var/folders/... on macOS;
 Linux CI will not see this)

pre-commit run --files web3/_utils/normalizers.py tests/core/middleware/test_name_to_address_middleware.py — all hooks green (black, flake8, isort, pydocstyle, mypy, autoflake, pyupgrade, blocklint).