doc(changelog): remove UTF symbols from pyproject.toml

The reason is that `pyproject.toml` is read in many contexts. These
symbols are niceties that nevertheless impact platform compatibility.
Reading the file with the default platform encoding on windows
(`cp1252`) fails, because these symbols cannot be mapped.

Software should be able to handle UTF, but we cannot afford to make a
point in this crucial file.

pyproject.toml

@@ -113,10 +113,10 @@ schema_pattern = "(?s)(ci|doc|feat|fix|perf|rf|style|test|chore|revert|bump)(\\(
 "^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"
+"BREAKING CHANGE" = "Breaking changes"
+doc = "Documentation"
+feat = "New features"
+fix = "Bug Fixes"
+test = "Tests"
+rf = "Refactorings"
+perf = "Performance improvements"