[Merged by Bors] - feat(RingTheory/MvPolynomial/MonomialOrder): add some variants of sPolynomial_mul_monomial

[Hagb]

This commit adds a variant sPolynomial_mul_monomial', using m.degree (monomial d c * p) instead of d + m.degree p, which are different in the edge case that one of c and p is 0.

A pair of variants about leadingTerm instead of monomial are also added.

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[github-actions]

PR summary 4d33172004

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

+ sPolynomial_leadingTerm_mul
+ sPolynomial_leadingTerm_mul'
+ sPolynomial_monomial_mul
+ sPolynomial_monomial_mul'
- sPolynomial_mul_monomial

You can run this locally as follows

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

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

The doc-module for script/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/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).

[erdOne]

Again weird lemmas for weird Gröbner bases.
Thanks!
maintainer merge

[github-actions]

🚀 Pull request has been placed on the maintainer queue by erdOne.

[jcommelin]

Thanks 🎉

bors merge

[mathlib-bors]

Pull request successfully merged into master.

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