fix: narrow jsonschema constraint to >=4.20,<4.21

- Update constraint from >=4.20,<5.0 to >=4.20,<4.21 for testing
- Regenerate poetry.lock with narrower constraint
- Testing if specific jsonschema 4.20.x version resolves CI failures

Co-Authored-By: AJ Steers <[email protected]>

Author: devin-ai-integration[bot]

poetry.lock

@@ -43,7 +43,7 @@ google-cloud-secret-manager = "^2.17.0"
 isodate = "~0.6.1"
 Jinja2 = "~3.1.2"
 jsonref = "~0.2"
-jsonschema = ">=4.20,<5.0"
+jsonschema = ">=4.20,<4.21"
 packaging = "*"  # Transitive dependency used directly in code
 pandas = "2.2.3"
 psutil = "6.1.0" # TODO: Remove if unused