WARN: Add FutureWarning for `DataFrame.to_latex`
Instead of #41648, which performs a refactor and adds the warning in the same PR, I am proposing adding the warning only for 1.4.0 and then in 2.0 there will be scope to make breaking changes and refactor the arguments signature.

looks fine can you add a whatsnew note in the deprecation section to message this. ping on green. I didn't stumble upon this until today; this warning is emitted every time a user uses this method even though this method is not deprecated. The message itself says the arguments _may_ change, and doesn't give any indication how. I think the bar for disrupting users (especially those that have a CI that fails on warnings) needs to be set higher. @attack68 do you have bandwidth/appetite to align DataFrame.to_latex and Styler.to_latex since 2.0 will be the next version? If not, I suppose we should remove this warning for 2.0 see https://github.com/pandas-dev/pandas/pull/47970#issuecomment-1320579957