chore: consolidate changelog "looks" in template

Before the mapping from change type keys to verbose names was in
`pyproject.toml`, but that file is quite full already. We need not
have it be concerned with the looks of changelog generation, when
most of that is in the template already.

.changelog.md.j2

@@ -4,8 +4,17 @@
 
 {% for change_key, changes in entry.changes.items() %}
 
+{% set change_key_map = {
+  'BREAKING CHANGE': '🪓 Breaking changes',
+  'doc': '📝 Documentation',
+  'feat': '💫 New features',
+  'fix': '🐛 Bug Fixes',
+  'test': '🛡 Tests',
+  'rf': '🏠 Refactorings',
+  'perf': '🚀 Performance improvements',
+} %}
 {% if change_key %}
-## {{ change_key }}
+## {{ change_key_map.get(change_key, change_key) }}
 {% endif %}
 {% set scopemap = {
   'changelog': 'Changelog',

pyproject.toml

@@ -202,12 +202,3 @@ schema_pattern = "(?s)(ci|doc|feat|fix|perf|rf|style|test|chore|revert|bump)(\\(
 "^BREAKING" = "MAJOR"
 "^feat" = "MINOR"
 "^fix" = "PATCH"
-
-[tool.commitizen.customize.change_type_map]
-"BREAKING CHANGE" = "Breaking changes"
-doc = "Documentation"
-feat = "New features"
-fix = "Bug Fixes"
-test = "Tests"
-rf = "Refactorings"
-perf = "Performance improvements"