sage

c0e0c378 -

gh-38636: fix something in quadratic forms fix #38633 ### :memo: Checklist - [x] The title is concise and informative. - [x] The description explains in detail what this PR is about. - [ ] I have linked a relevant issue or discussion. - [ ] I have created tests covering the changes. - [ ] I have updated the documentation and checked the documentation preview. URL: https://github.com/sagemath/sage/pull/38636 Reported by: Frédéric Chapoton Reviewer(s): Travis Scrimshaw