[MNT] [Dependabot](deps-dev): Update holidays requirement from <0.43,…

…>=0.29 to >=0.29,<0.44 (#5965)

Updates the requirements on
[holidays](https://github.com/vacanza/python-holidays) to permit the
latest version.

pyproject.toml

@@ -201,7 +201,7 @@ regression = [
 transformations = [
   'esig<0.10,>=0.9.7; python_version < "3.11"',
   "filterpy<1.5,>=1.4.5",
-  "holidays>=0.29,<0.43",
+  "holidays>=0.29,<0.44",
   "mne>=1.5,<1.7",
   'numba<0.59,>=0.53; python_version < "3.12"',
   "pycatch22>=0.4,<0.4.4",