fd_t::resize does not update internal size to new size

[lethalbit]

I was inspecting some code and noticed that the resize call in fd_t does not change the internal length tracking for the open file, causing a desync if resize is ever called.

substrate/substrate/fd

Lines 122 to 124 in d0ea63f

	SUBSTRATE_NO_DISCARD(bool resize(const off_t newSize) const noexcept)
	{ return internal::fdtruncate(fd, newSize) == 0; }