update CHANGELOG for v7.1.1 [ci skip]

Author: juergba

CHANGELOG.md

@@ -1,3 +1,17 @@
+# 7.1.1 / 2020-03-18
+
+## :lock: Security Fixes
+
+- [#4204](https://github.com/mochajs/mocha/issues/4204): Update dependencies mkdirp, yargs-parser and yargs ([**@juergba**](https://github.com/juergba))
+
+## :bug: Fixes
+
+- [#3660](https://github.com/mochajs/mocha/issues/3660): Fix `runner` listening to `start` and `end` events ([**@juergba**](https://github.com/juergba))
+
+## :book: Documentation
+
+- [#4190](https://github.com/mochajs/mocha/issues/4190): Show Netlify badge on footer ([**@outsideris**](https://github.com/outsideris))
+
 # 7.1.0 / 2020-02-26
 
 ## :tada: Enhancements