DOC: Examples added for float_format in to_csv documentation

[Uvi-12]

Closes #60363

[Uvi-12]

@rhshadrach Please check if the examples are appropriate.

[mroeschke]

Could you undo all the changes in this file? They don't appear related to the linked issue

[Uvi-12]

Some commits in this PR #60457 were mistakenly added but are meant for issue #60446. I am new to open-source contributions and apologize for the confusion.

Could you please guide me on how I can avoid this mistake in the future?

[mroeschke]

Suggested change

	Format floating-point numbers using float_format:
	- Format floats to two decimal places:
	>>> df.to_csv("out1.csv", float_format="%.2f") # doctest: +SKIP
	- Use scientific notation:
	>>> df.to_csv("out2.csv", float_format="{:.2e}".format) # doctest: +SKIP
	Format floats to two decimal places:
	>>> df.to_csv("out1.csv", float_format="%.2f") # doctest: +SKIP
	Format floats using scientific notation:
	>>> df.to_csv("out2.csv", float_format="{:.2e}".format) # doctest: +SKIP

[Uvi-12]

@mroeschke The reviewed changes are corrected, have a check and let me know if further changes are required.

[Uvi-12]

@mroeschke The code is changed accordingly to the reviewed changes, don't know why the tests are failing, can you please help me with it?

[mroeschke]

Suggested change

	>>> df.to_csv("out2.csv", float_format="{:.2e}".format) # doctest: +SKIP
	>>> df.to_csv("out2.csv", float_format="{{:.2e}}".format) # doctest: +SKIP

[mroeschke]

Thanks @Uvi-12

[Uvi-12]

@mroeschke Thank you for the reviews, that helped a lot.