Update schema-salad requirement

Updates the requirements on [schema-salad](https://github.com/common-workflow-language/schema_salad) to permit the latest version.
- [Release notes](https://github.com/common-workflow-language/schema_salad/releases)
- [Commits](common-workflow-language/schema_salad@5.0.20200220195218...8.0.20210624154013)

---
updated-dependencies:
- dependency-name: schema-salad
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

requirements.txt

@@ -1,3 +1,3 @@
-schema-salad >= 5.0.20200220195218, <8
+schema-salad >= 5.0.20200220195218, < 9
 junit-xml >= 1.8
 pytest < 7

setup.py

@@ -15,7 +15,7 @@
 except ImportError:
     tagger = egg_info_cmd.egg_info
 
-install_requires = ["schema-salad >= 5.0.20200220195218, < 8", "junit-xml >= 1.8"]
+install_requires = ["schema-salad >= 5.0.20200220195218, < 9", "junit-xml >= 1.8"]
 
 needs_pytest = {"pytest", "test", "ptr"}.intersection(sys.argv)
 pytest_runner = ["pytest < 6", "pytest-runner < 5"] if needs_pytest else []