Changed TIFF tag 33723 length to 1

[radarhere]

Resolves #2278

The issue reports that a TIFF image cannot be opened and saved - AttributeError: 'tuple' object has no attribute 'ljust'. The problem comes from tag 33723 - https://www.awaresystems.be/imaging/tiff/tifftags/iptc.html

Pillow/src/PIL/TiffTags.py

Line 181 in ab8955b

33723: ("IptcNaaInfo", UNDEFINED, 0),

Loading and saving existing test image hopper.Lab.tif currently triggers the same bug.

This PR changes the tag length to 1, allowing the image to save without an error.

It also produces nicer values for the tag.

from PIL import Image
im = Image.open("00000001.tif")
print(im.tag_v2[33723])
im = Image.open("Tests/images/hopper.Lab.tif")
print(im.tag_v2[33723])

Currently gives

(b'\x1c\x01Z\x00\x03\x1b%G\x1c\x02\x00\x00\x02\x00\x00\x1c\x02P\x00\tULB Halle\x1c\x02t\x00\r(c) ULB Halle',)
(b'\x1c\x01Z\x00\x03\x1b%G\x1c\x02\x00\x00\x02\xcf\xc0',)

But with this PR, it gives

b'\x1c\x01Z\x00\x03\x1b%G\x1c\x02\x00\x00\x02\x00\x00\x1c\x02P\x00\tULB Halle\x1c\x02t\x00\r(c) ULB Halle'
b'\x1c\x01Z\x00\x03\x1b%G\x1c\x02\x00\x00\x02\xcf\xc0'