feat(Combinatorics/SimpleGraph): add lemma SimpleGraph.length_cycleBypass_le

[IvanRenison]

---

[github-actions]

PR summary 11476c36a7

Import changes for modified files

No significant changes to the import graph

Import changes for all files

Files	Import difference

---

Declarations diff

+ length_cycleBypass_le

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.

---

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).

[YaelDillies]

Can you deduce this from the fact that w.cycleBypass.edges is a sublist of w.edges? Then you can also golf edges_cycleBypass_subset with it

[IvanRenison]

Yes, I can. However, I see that #37577 is already adding the theorem that w.cycleBypass.edges is a sublist of w.edges, and, besides doing it for this lemma, it should also be done for length_bypass_le and some other lemmas in other files. So, is it okay if I do it in a separate pull request depending on #37577 (Or if we ask SnirBroshi to do it)?

[YaelDillies]

Do what you want between the two of you, so long as I don't have to approve of the suboptimal proof 😄

My two cents is that your PR could be absorbed into Snir's given how small it is.