feat(AlgebraicTopology): homology of contractible spaces

[erdOne]

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[github-actions]

PR summary 5289bf289a

Import changes for modified files

Dependency changes

File	Base Count	Head Count	Change
Mathlib.AlgebraicTopology.SingularHomology.HomotopyInvarianceTopCat	1717	1720	+3 (+0.17%)

Import changes for all files

Files	Import difference
Mathlib.AlgebraicTopology.SingularHomology.HomotopyInvarianceTopCat	3

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Declarations diff

+ instance (X : TopCat.{w}) [ContractibleSpace X] (R : C) (n : ℕ) :
+ instance : Unique (⊤_ TopCat.{u})
+ isZero_singularHomologyFunctor_of_contractibleSpace
+ singularHomologyFunctorHomotopyEquiv
+ singularHomologyFunctorZeroOfContractibleSpace
+ singularHomologyFunctor_obj_map_eq_of_homotopic

You can run this locally as follows

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

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

The doc-module for scripts/pr_summary/declarations_diff.sh contains some details about this script.

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No changes to technical debt.

You can run this locally as

./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).