[Merged by Bors] - feat: if an L^p space is complete, so is its target space unless the measure is zero

[sgouezel]

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[github-actions]

PR summary b5df2bea62

Import changes for modified files

No significant changes to the import graph

Import changes for all files

Files	Import difference
5 files Mathlib.MeasureTheory.Function.ConvergenceInMeasure Mathlib.MeasureTheory.Function.LpOrder Mathlib.MeasureTheory.Function.LpSpace.Basic Mathlib.MeasureTheory.Function.LpSpace.Complete Mathlib.MeasureTheory.Function.LpSpace.Indicator	1
Mathlib.MeasureTheory.Function.LpSpace.CompleteOfCompleteLp (new file)	2261

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Declarations diff

+ AEFinStronglyMeasurable.exists_measurableSet_measure_pos_lt_top
+ FinStronglyMeasurable.exists_measurableSet_measure_pos_lt_top
+ compLpL₂
+ compLpL₂_apply_apply
+ compLpₗ₂
+ completeSpace_of_completeSpace_Lp
+ nontrivial_Lp_real_of_nontrivial_Lp
+ norm_compLpL₂_le

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.

[sgouezel]

Thanks for the review!

[EtienneC30]

Thanks!
maintainer merge

[github-actions]

🚀 Pull request has been placed on the maintainer queue by EtienneC30.

[RemyDegenne]

Thanks!
bors r+

[mathlib-bors]

Pull request successfully merged into master.

Build succeeded:

• ci (staging) / Lint style
• ci (staging) / Post-CI job
• ci (staging) / Post-Build Step
• ci (staging) / Build