chore(renovate): group release-it packages

group release-it and related packages. with the release of release-it
v18, the conventional changelog plugin needs to be updated in tandem,
as it has a peer dep on release-it. grouping them ought to fix the error
in github where renovate cannot perform the upgrade due to failed peer
deps.

renovate.json5

@@ -39,6 +39,10 @@
       groupName: 'Vitest',
       matchPackageNames: ['@vitest{/,}**', 'vitest{/,}**'],
     },
+    {
+      groupName: 'Release It',
+      matchPackageNames: ['release-it', '@release-it/*'],
+    },
     {
       // auto-merge anything that's not a major version bump
       matchUpdateTypes: ['minor', 'patch', 'pin', 'digest'],