Silent loading failure, Stripped `next="..."` part from column entry.

[MvGulik]

More general info than bug I figure, as this is messing around with the ws source code.

Wanted to reset the new-cell numbering for all columns. So I just removed the related next"<n>" parts from the ws file. (also to see if that would work ok)
This did however resulted in a total silent nip4 loading failure for the ws file. (ie: including being silent in terminal mode)

... next="1" is it.

(next="" will start nip4 in 'new works space mode' with at least a "unable to execute" displayed error message.)(was Nip4: 9.0.18 related)

Locals:
	Nip4: 9.0.18 (Flatpak), libvips 8.19.0
	OS: Linux, Mint (21.3), Cinnamon (6.0.4), Kernel (5.15.0-173-generic)

[MvGulik]

Experimented a bit more with it: (nip4: 9.0.18)

• Empty name="": Loads ok. (_acts as name="0" => first new cell will be named as "A0"(if free).
• Negative name="-123": Loads ok. (new cells will start with "A-123", counting 'up' to zero ("A-122","A-121",...)
• +Text name="abc" or name="ab-123cd": Loads ok. (_also acts as name="0")

(Additional side effects of zero or negatives unknown. Although non expected.)