DEP: Add optional format-checking dependencies for jsonschema

setup.py

@@ -157,7 +157,7 @@ def setup_package():
         python_requires='>=3.7',
         install_requires=["linkahead>=0.13.1",
                           "jsonref",
-                          "jsonschema>=4.4.0",
+                          "jsonschema[format]>=4.4.0",
                           "numpy>=1.17.3",
                           "openpyxl>=3.0.7",
                           "pandas>=1.2.0",