deps(autogen): set packed = false on field_behavior extension (#2101)

- [ ] Regenerate this pull request now.

PiperOrigin-RevId: 604675854

Source-Link: https://togithub.com/googleapis/googleapis/commit/42c04fea4338ba626095ec2cde5ea75827191581

Source-Link: https://togithub.com/googleapis/googleapis-gen/commit/a1ed8a97a00d02fe456f6ebd4160c5b2b000ad75
Copy-Tag: eyJwIjoiLmdpdGh1Yi8uT3dsQm90LnlhbWwiLCJoIjoiYTFlZDhhOTdhMDBkMDJmZTQ1NmY2ZWJkNDE2MGM1YjJiMDAwYWQ3NSJ9

Author: gcf-owl-bot[bot]