Pin deepdiff to later version

Pins deepdiff to the penultimate version (7) which fixes a PyYAML
dependency issue with Cython [1] but which does not have the redesigned
output interface from version 8. This commit should fix CI for Python
versions 3.10 and 3.11.

[1] seperman/deepdiff#406

pyproject.toml

@@ -30,7 +30,7 @@ dependencies = [
 test = [
     "coverage[toml] >=5.2.1, ==5.*",
     "cram >=0.7, ==0.*",
-    "deepdiff[cli] >=5.2.0, ==5.*",
+    "deepdiff[cli] >=7.0.0, ==7.*",
     "flake8 >=3.9.0, ==3.*",
     "pylint >=2.14.5, ==2.*",
 ]