Docs: Remove undocumented zero_division reference from dice_score docstring.

[rittik9]

What does this PR do?

Fixes #3258

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• Did you make sure to update the docs?
• Did you write any new necessary tests?

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---

📚 Documentation preview 📚: https://torchmetrics--3279.org.readthedocs.build/en/3279/

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 32%. Comparing base (fd967c0) to head (7412407).

❗ There is a different number of reports uploaded between BASE (fd967c0) and HEAD (7412407). Click for more details.

HEAD has 408 uploads less than BASE

Flag	BASE (fd967c0)	HEAD (7412407)
gpu	2	0
unittest	2	0
Windows	14	2
cpu	118	17
python3.12	28	4
torch2.8.0+cpu	21	3
torch2.0.1+cpu	21	3
python3.10	83	12
torch2.8.0	7	1
macOS	20	3
Linux	84	12
torch2.7.1+cpu	14	2
torch2.4.1+cpu	7	1
torch2.2.2+cpu	7	1
torch2.0.1	13	2
torch2.5.1+cpu	7	1
torch2.1.2+cpu	7	1
torch2.6.0+cpu	7	1
torch2.3.1+cpu	7	1
python3.9	7	1

Additional details and impacted files

@@           Coverage Diff            @@
##           master   #3279     +/-   ##
========================================
- Coverage      37%     32%     -5%     
========================================
  Files         364     349     -15     
  Lines       20096   19901    -195     
========================================
- Hits         7520    6376   -1144     
- Misses      12576   13525    +949     

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[justusschock]

Hey @rittik9 , thanks for your work here. Would you mind just pushing an empty commit to trigger CI again? There have been fixes to it in the last week :)