feat(ConditionallyCompleteLattice/Indexed): add binary versions of lemmas

[lua-vr]

Add binary versions of some of the lemmas. Those are useful when the domain is indexed over the members of a set.

From the Carleson project.

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[github-actions]

PR summary 8eb1ca9e64

Import changes for modified files

No significant changes to the import graph

Import changes for all files

Files	Import difference

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Declarations diff

+ ciSup₂_le
+ ciSup₂_le'
+ exists_lt_of_lt_ciSup₂
+ exists_lt_of_lt_ciSup₂'
- le_ciInf

You can run this locally as follows

## from your `mathlib4` directory:
git clone https://github.com/leanprover-community/mathlib-ci.git ../mathlib-ci

## summary with just the declaration names:
../mathlib-ci/scripts/pr_summary/declarations_diff.sh <optional_commit>

## more verbose report:
../mathlib-ci/scripts/pr_summary/declarations_diff.sh long <optional_commit>

The doc-module for scripts/pr_summary/declarations_diff.sh in the mathlib-ci repository contains some details about this script.

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No changes to strong technical debt.

No changes to weak technical debt.

[grunweg]

Some minor comments.

[lua-vr]

-awaiting-author

[SnirBroshi]

Thanks!

[mathlib-merge-conflicts]

This pull request has conflicts, please merge master and resolve them.

[mathlib-merge-conflicts]

This pull request has conflicts, please merge master and resolve them.

[JovanGerb]

Please also add the dual of the theorem. Otherwise it will be more annoying when we do tag the whole file with to_dual.

[SnirBroshi]

Sadly ConditionallyCompleteLinearOrderBot has no dual, so none of the theorems around here can be to_dualized

[JovanGerb]

Ah that's too bad, in that case ignore my comment.

[lua-vr]

@JovanGerb in #38938 I made an attempt to tag the whole file with to_dual (but this section was not included)