feat(Combinatorics/SimpleGraph): add several lemmas about when Walk.bypass and Walk.cycleBypass do nothing

[IvanRenison]

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• depends on: feat(Combinatorics/SimpleGraph): add lemma SimpleGraph.length_cycleBypass_le #37505
• depends on: feat(Data/List): add lemma List.notMem_subset #37561

[github-actions]

PR summary 6a7332dd00

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

+ IsCycle.cycleBypass_eq_self
+ IsPath.bypass_eq_self
+ IsTrail.cycleBypass_eq_self_iff_isCycle_or_nil
+ IsTrail.length_cycleBypass_lt_iff_not_isCycle_and_not_nil
+ bypass_eq_self_iff_isPath
+ bypass_eq_self_iff_length_le
+ cycleBypass_eq_self_iff_length_le
+ cycleBypass_eq_self_of_length_le
+ length_bypass_lt_iff_not_isPath
+ length_cycleBypass_le
+ notMem_subset

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).

[mathlib-dependent-issues]

This PR/issue depends on:

• feat(Combinatorics/SimpleGraph): add lemma SimpleGraph.length_cycleBypass_le #37505
• feat(Data/List): add lemma List.notMem_subset #37561
  By Dependent Issues (🤖). Happy coding!