requirements[dev]: Upgrade mypy from ~=1.4.0 to ~=1.5.0.

The strict-concatenate option is now deprecated, so replaced by
extra-checks, in pyproject.toml.

Author: neiljp

pyproject.toml

@@ -90,7 +90,8 @@ warn_unused_ignores = true
 warn_return_any = false
 no_implicit_reexport = true  # NOTE: Disabled explicitly for tests/ in run-mypy
 strict_equality = true
-strict_concatenate = true
+
+extra_checks = true
 
 enable_error_code = [
     "redundant-expr",

setup.py

@@ -42,7 +42,7 @@ def long_description():
 
 typing_deps = [
     "lxml-stubs",
-    "mypy~=1.4.0",
+    "mypy~=1.5.0",
     "types-beautifulsoup4",
     "types-pygments",
     "types-python-dateutil",