Chore(deps-dev): Update zope-testrunner requirement

Updates the requirements on [zope-testrunner](https://github.com/zopefoundation/zope.testrunner) to permit the latest version.
- [Changelog](https://github.com/zopefoundation/zope.testrunner/blob/master/CHANGES.rst)
- [Commits](zopefoundation/zope.testrunner@5.0...7.0)

---
updated-dependencies:
- dependency-name: zope-testrunner
  dependency-type: direct:development
...

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

Author: dependabot[bot]

setup.py

@@ -74,7 +74,7 @@ def read(path):
             "pytz",
             "zc.customdoctests>=1.0.1,<2",
             "zope.testing>=4,<6",
-            "zope.testrunner>=5,<7",
+            "zope.testrunner>=5,<8",
         ],
     },
     python_requires=">=3.6",