ci: Enable Renovate automerge for npm

The renovate bot has the ability to merge package changes that pass ci
testing and follow semver minor updates (non-breaking changes). I've
been merging renovate packages for the past six months or so with no
problems that weren't caught using the test suite, so I feel confident
in letting the bot take over merging.

.github/renovate.json5

@@ -4,5 +4,13 @@
         "github>nf-core/ops//.github/renovate/default.json5",
         "config:recommended",
         "schedule:weekly"
+    ],
+    "packageRules": [
+        {
+            "matchManagers": ["npm"],
+            "automerge": true,
+            "matchUpdateTypes": ["minor", "patch", "pin", "digest"],
+            "schedule": ["before 5am daily"]
+        }
     ]
 }