`IPv6Network.next_network()` raises the wrong error when addresses run out

Bug description:

_BaseNetwork.next_network() guards address-space exhaustion with except OverflowError, which only the IPv4 path raises, so on IPv6 the internal ValueError from _string_from_ip_int() escapes instead.

from ipaddress import IPv4Network, IPv6Network

for net in (IPv4Network('255.255.255.0/24'),
            IPv6Network('ffff:ffff:ffff:ffff:ffff:ffff:ffff:0/112')):
    try:
        net.next_network()
    except ValueError as e:
        print(f"{net}: {e}")

Output:

255.255.255.0/24: out of address space, cannot make another /24 network
ffff:ffff:ffff:ffff:ffff:ffff:ffff:0/112: IPv6 address is too large

Expected: out of address space, cannot make another /112 network, the message Doc/library/ipaddress.rst gives for next_network().

CPython versions tested on:

CPython main branch

Operating systems tested on:

Linux

Linked PRs

• gh-156681
• gh-157280

Xem xét _BaseNetwork.next_network() và phần diễn đạt về next_network() trong Doc/library/ipaddress.rst, sau đó tái hiện các ví dụ IPv4 và IPv6 từ issue. Được xem là hoàn tất khi tình trạng cạn kiệt không gian địa chỉ IPv6 báo cáo thông báo được tài liệu hóa “out of address space” cho mạng /112 thay vì “IPv6 address is too large”.