Bump requirement of directory converters

[bernt-matthias]

with conda I get (because it chooses a python without imghdr). We dropped the need for this module in 24.2 #18449

Traceback (most recent call last):
  File "<string>", line 1, in <module>
    from galaxy.util.compression_utils import CompressedFile; CompressedFile('/tmp/tmp3v2nuot4/files/a/9/7/dataset_a97aebb4-46f7-47a9-b418-11ff1deeed74.dat').extract('.')
    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/berntm/miniforge3/envs/[email protected]/lib/python3.13/site-packages/galaxy/util/compression_utils.py", line 29, in <module>
    from .checkers import (
    ...<2 lines>...
    )
  File "/home/berntm/miniforge3/envs/[email protected]/lib/python3.13/site-packages/galaxy/util/checkers.py", line 20, in <module>
    from galaxy.util.image_util import image_type
  File "/home/berntm/miniforge3/envs/[email protected]/lib/python3.13/site-packages/galaxy/util/image_util.py", line 3, in <module>
    import imghdr
ModuleNotFoundError: No module named 'imghdr'

How to test the changes?

(Select all options that apply)

• I've included appropriate automated tests.
• This is a refactoring of components with existing test coverage.
• Instructions for manual testing are as follows:
  1. [add testing steps and prerequisites here if you didn't write automated tests covering all your changes]

License

• I agree to license these and all my past contributions to the core galaxy codebase under the MIT license.

[nsoranzo]

I don't think we need to bump the tool versions since these are internal tools, but just mentioning it in case someone disagrees.

[github-actions]

This PR was merged without a "kind/" label, please correct.