chore(Algebra/Homology/HomotopyCategory/Shift): clean up most of set_options

[Whysoserioushah]

If we want every set_option gone from this file, especially gone from this instance: CategoryTheory.Functor.commShiftMapCochainComplex then we need to set the reducibility of Functor.mapHomologicalComplex into reducible, this together with ContCohomology may indicate that we want it as an abbrev.

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[github-actions]

PR summary f1c5dfd630

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 (regex)

No declarations were harmed in the making of this PR! 🐙

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.

Declarations diff (Lean)

✅ Lean-aware diff — post-build, computed from the Lean environment (commit f1c5dfd).

• +2 new declarations
• −0 removed declarations

+CochainComplex.HomComplex.Cochain.leftShiftAddEquiv.congr_simp
+CochainComplex.HomComplex.Cochain.rightShiftAddEquiv.congr_simp

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Decrease in strong tech debt: (relative, absolute) = (12.76, 0.01)

Current number	Change	Type (strong)
4351	-15	backward.defeqAttrib.useBackward
6969	-14	backward.isDefEq.respectTransparency
3977	-10	backward.isDefEq.respectTransparency.types

No changes to weak technical debt.

Current commit f1c5dfd630
Reference commit 20a3b032e0

This script lives in the mathlib-ci repository. To run it locally, from your mathlib4 directory:

git clone https://github.com/leanprover-community/mathlib-ci.git ../mathlib-ci
../mathlib-ci/scripts/reporting/technical-debt-metrics.sh pr_summary

• The relative value is the weighted sum of the differences with weight given by the inverse of the current value of the statistic.
• The absolute value is the relative value divided by the total sum of the inverses of the current values (i.e. the weighted average of the differences).

[Whysoserioushah]

!radar

[leanprover-radar]

Benchmark results for f1c5dfd against 20a3b03 are in. No significant results found. @Whysoserioushah

• 🟥 build//instructions: +6.3G (+0.00%)

Small changes (2🟥)

• 🟥 build/module/Mathlib.Algebra.Homology.HomotopyCategory.Shift//instructions: +2.4G (+11.52%)
• 🟥 build/module/Mathlib.CategoryTheory.Sites.SheafCohomology.Basic//instructions: +2.9G (+7.15%)

[joelriou]

I believe this should be a global implicit_reducible definition. (Arguably, also HomotopyCategory.quotient below: but do not take too much time on that one as it may require lots of fixes.)

[Whysoserioushah]

I believe so too! But is that change better to be in another PR?