Add Jungfrau 9M detector size constants

[ndevenish]

The i24 jungfrau is a Jungfrau 9M: 3108 x 3262 pixels of 75um, so 233.1 x 244.65 mm.

Instructions to reviewer on how to test:

1. import dodal.devices.detector.det_dim_constants
2. print(dodal.devices.detector.det_dim_constants.ALL_DETECTORS["JUNGFRAU_9M"])

Checks for reviewer

• Would the PR title make sense to a scientist on a set of release notes
• If a new device has been added does it follow the standards
• If changing the API for a pre-existing device, ensure that any beamlines using this device have updated their Bluesky plans accordingly
• Have the connection tests for the relevant beamline(s) been run via dodal connect ${BEAMLINE}

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 99.20%. Comparing base (c9355dd) to head (b2f51bf).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2184   +/-   ##
=======================================
  Coverage   99.20%   99.20%           
=======================================
  Files         367      367           
  Lines       14589    14597    +8     
=======================================
+ Hits        14473    14481    +8     
  Misses        116      116           

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