Generate component renovate.json in post-gen-project hook

[simu]

We expect that writing more complex package rules as Jinja2 templates in JSON will quickly become unreadable, so we move generating the component's renovate.json to the template's pos-gen-project Python hook where we can generate the desired package rules and other conditional configurations more easily.

Follow-up to #101

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  changelog.
  The PR has a meaningful description that sums up the change. It will be
  linked in the changelog.
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[simu]

Note that this changes the JSON layout a bit:

--- base/renovate.json	2024-06-06 13:45:07.245014870 +0200
+++ feat/renovate.json	2024-06-06 13:47:36.637434662 +0200
@@ -11,17 +11,23 @@
     "commands": [
       "make gen-golden-all"
     ],
-    "fileFilters": [ "tests/golden/**" ],
+    "fileFilters": [
+      "tests/golden/**"
+    ],
     "executionMode": "update"
   },
-  "suppressNotifications": [ "artifactErrors" ],
+  "suppressNotifications": [
+    "artifactErrors"
+  ],
   "labels": [
     "dependency"
   ],
   "separateMinorPatch": true,
   "packageRules": [
     {
-      "matchUpdateTypes": ["patch"],
+      "matchUpdateTypes": [
+        "patch"
+      ],
       "matchCurrentVersion": "!/^v?0\\./",
       "automerge": true,
       "platformAutomerge": false,

[bastjan]

Maybe we should move the whole renovate.json dict into python?

[simu]

Maybe we should move the whole renovate.json dict into python?

I've considered that, but I'm not sure if having the whole renovate.json in the post-gen-project hook would be more or less surprising than the current mixed approach.

[simu]

follow-up: see ebd82f5 for a draft implementation which fully generates the renovate.json from the post-gen-project hook.

After staring at it for a bit, I think I'll use that version (+ a note in the template repo README to reduce confusion levels if someone wants to adjust the templated renovate.json).

[bastjan]

i like that we now can add comments as we like 👍