fix 404 link on devel landing page (#12316)

Author: drammock

CONTRIBUTING.md

@@ -5,5 +5,5 @@ MNE-Python is maintained by a community of scientists and research labs. The pro
 
 Users and contributors to MNE-Python are expected to follow our [code of conduct](https://github.com/mne-tools/.github/blob/main/CODE_OF_CONDUCT.md).
 
-The [contributing guide](https://mne.tools/dev/install/contributing.html) has details on the preferred contribution workflow
+The [contributing guide](https://mne.tools/dev/development/contributing.html) has details on the preferred contribution workflow
 and the recommended system configuration for a smooth contribution/development experience.

doc/development/index.rst

@@ -24,7 +24,7 @@ experience.
 .. _`opening an issue`: https://github.com/mne-tools/mne-python/issues/new/choose
 .. _`MNE Forum`: https://mne.discourse.group
 .. _`code of conduct`: https://github.com/mne-tools/.github/blob/main/CODE_OF_CONDUCT.md
-.. _`contributing guide`: https://mne.tools/dev/install/contributing.html
+.. _`contributing guide`: https://mne.tools/dev/development/contributing.html
 
 .. toctree::
    :hidden: