[add] py-metomi-isodatetime: new recipe, required by py-cylc-flow (#39990)

* [add] py-metomi-isodatetime: new recipe, required by py-cylc-flow

* py-metomi-isodatetime: use sources from pypi instead of github

var/spack/repos/builtin/packages/py-metomi-isodatetime/package.py

@@ -0,0 +1,19 @@
+# Copyright 2013-2023 Lawrence Livermore National Security, LLC and other
+# Spack Project Developers. See the top-level COPYRIGHT file for details.
+#
+# SPDX-License-Identifier: (Apache-2.0 OR MIT)
+
+from spack.package import *
+
+
+class PyMetomiIsodatetime(PythonPackage):
+    """Python ISO 8601 date time parser and data model/manipulation utilities."""
+
+    homepage = "https://github.com/metomi/isodatetime"
+    pypi = "metomi-isodatetime/metomi-isodatetime-1!3.0.0.tar.gz"
+
+    maintainers("LydDeb")
+
+    version("3.0.0", sha256="2141e8aaa526ea7f7f1cb883e6c8ed83ffdab73269658d84d0624f63a6e1357e")
+
+    depends_on("py-setuptools", type="build")