Update changelog

Author: lyashevska

CHANGELOG.md

@@ -17,6 +17,7 @@
 * Make online documentation optional [#476](https://github.com/NLeSC/python-template/pull/476)
 
 ### Changed
+* Updated .gitignore [#622](https://github.com/NLeSC/python-template/pull/622)
 * added value field to license options [#617](https://github.com/NLeSC/python-template/pull/617)
 * fix filename typo of githooks [#611](https://github.com/NLeSC/python-template/pull/609)
 * next_steps.md is shown as a copier message [#609](https://github.com/NLeSC/python-template/pull/609)