Rename lazy-loader to lazy_loader (#4610)

`lazy_loader` seems to be the correct project name.

packages/lazy-loader/meta.yaml

@@ -1,16 +0,0 @@
-package:
-  name: lazy-loader
-  version: "0.3"
-  top-level:
-    - lazy_loader
-source:
-  url: https://files.pythonhosted.org/packages/a1/c3/65b3814e155836acacf720e5be3b5757130346670ac454fee29d3eda1381/lazy_loader-0.3-py3-none-any.whl
-  sha256: 1e9e76ee8631e264c62ce10006718e80b2cfc74340d17d1031e0f84af7478554
-requirements:
-  run:
-    - packaging
-about:
-  home: https://github.com/scientific-python/lazy_loader
-  PyPI: https://pypi.org/project/lazy-loader
-  summary: lazy_loader
-  license: BSD License

packages/mne/meta.yaml

@@ -12,7 +12,7 @@ requirements:
     - scipy
     - setuptools
     - decorator
-    - lazy-loader
+    - lazy_loader
     - packaging
 about:
   home: https://mne.tools/dev/