feat: add finitely presented instance for free groups

[pacastega]

Add IsFinitelyPresented instance for free groups

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This commit adds a IsFinitelyPresented instance for free groups over Fin n.
@homeowmorphism

[github-actions]

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[github-actions]

PR summary f8770bc8b0

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

+ Subgroup.isNormalClosureFG_bot
+ instance {n : ℕ} : Group.IsFinitelyPresented (FreeGroup (Fin n)) := by

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).

[github-actions]

✅ PR Title Formatted Correctly

The title of this PR has been updated to match our commit style conventions.
Thank you!

[tb65536]

Can you add a commit message above the line in the PR description?