Add logic to generate Renovate postUpgradeTasks

This commit adds logic to the `renovate.json` template in the component
template to generate section `postUpgradeTasks` when golden tests are
enabled when creating a component with `commodore component new`.

commodore/component-template/{{ cookiecutter.slug }}/renovate.json

@@ -4,6 +4,20 @@
     ":gitSignOff",
     ":disableDependencyDashboard"
   ],
+{%- if cookiecutter.add_golden == "y" %}
+  "postUpgradeTasks": {
+    "commands": [
+{%- if cookiecutter.add_matrix == "y" %}
+      "make gen-golden -e instance=defaults"
+{%- else %}
+      "make gen-golden"
+{%- endif %}
+    ],
+    "fileFilters": [ "tests/golden/**" ],
+    "executionMode": "update"
+  },
+  "suppressNotifications": [ "artifactErrors" ],
+{%- endif %}
   "labels": [
     "dependency"
   ]

tests/test_component_template.py

@@ -1,6 +1,7 @@
 """
 Tests for component new command
 """
+import json
 import os
 import pytest
 import yaml
@@ -140,6 +141,20 @@ def test_run_component_new_command(
             else:
                 assert run_step["run"] == "make golden-diff"
 
+    with open(
+        tmp_path / "dependencies" / component_name / "renovate.json"
+    ) as renovatejson:
+        renovateconfig = json.load(renovatejson)
+        assert ("postUpgradeTasks" in renovateconfig) == has_golden
+        if has_golden:
+            assert len(renovateconfig["postUpgradeTasks"]["commands"]) == 1
+            cmd = renovateconfig["postUpgradeTasks"]["commands"][0]
+            expected_cmd = {
+                "--matrix-tests": "make gen-golden -e instance=defaults",
+                "--no-matrix-tests": "make gen-golden",
+            }
+            assert cmd == expected_cmd[matrix]
+
 
 def test_run_component_new_command_with_name(tmp_path: P):
     """