Fix typo on estimated_stepping_batches property

[afspies]

Typo fix

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📚 Documentation preview 📚: https://pytorch-lightning--19847.org.readthedocs.build/en/19847/

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 53%. Comparing base (785f15d) to head (ab9666d).
Report is 104 commits behind head on master.

❗ There is a different number of reports uploaded between BASE (785f15d) and HEAD (ab9666d). Click for more details.

HEAD has 406 uploads less than BASE

Flag	BASE (785f15d)	HEAD (ab9666d)
python3.10	34	11
cpu	118	22
lightning	72	15
pytest	76	2
gpu	4	2
lightning_fabric	19	0
python3.11	40	5
python3.8	24	6
pytorch_lightning	19	9
examples	9	0
app	9	0
tpu	1	0
pytorch2.0	24	11
pytest-full	47	22
pytorch2.1	12	6
pytorch2.3	6	2
pytorch2.2	5	3
lightning_app	3	0

Additional details and impacted files

@@            Coverage Diff             @@
##           master   #19847      +/-   ##
==========================================
- Coverage      84%      53%     -31%     
==========================================
  Files         426      418       -8     
  Lines       35256    35103     -153     
==========================================
- Hits        29598    18697   -10901     
- Misses       5658    16406   +10748     

[awaelchli]

Thank you @afspies!