Ensure pre-commit uses LTS version of node

Since Node 23 came out, fresh installs or updates to our pre-commit hooks
will fail for eslint. This is because pre-commit will pick the very new
version of Node, because we haven't told it not to.

This change tells pre-commit to use the LTS version installed on the system,
which will match what we use for main Bedrock

.pre-commit-config.yaml

@@ -8,6 +8,10 @@ exclude: >
     | bedrock/externalfiles/files_cache
     | git-repos
   )
+
+default_language_version:
+  node: lts
+
 repos:
   # Note: hooks that add content must run before ones which check formatting, lint, etc
   - repo: https://github.com/pre-commit/pre-commit-hooks