cwltest 2.1.20210626101542 allow newer schema-salad

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](https://github.com/common-workflow-language/schema_salad/compare/5.0.20200220195218...8.0.20210624154013)

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

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