Merge pull request #516 from glemaitre/spelling_contributing_guide

docs: Fix spelling in the contributing guide

.github/CONTRIBUTING.md

@@ -14,7 +14,7 @@ Where might you answer user questions? Some of the forums for Q&A on **great_tab
 
 ### Making Pull Requests
 
-Should you consider making a pull request (PR), please file an issue first and explain the problem in some detail. If the PR is an enhancement, detail how the change would make things better for package users. Bugfix PRs also requre some explanation about the bug and how the proposed fix will remove that bug. A great way to illustrate the bug is to include an MRE. While all this upfront work prior to preparing a PR can be time-consuming it opens a line of communication with the package authors and the community, perhaps leading to a better enhancement or more effective fixes!
+Should you consider making a pull request (PR), please file an issue first and explain the problem in some detail. If the PR is an enhancement, detail how the change would make things better for package users. Bugfix PRs also require some explanation about the bug and how the proposed fix will remove that bug. A great way to illustrate the bug is to include an MRE. While all this upfront work prior to preparing a PR can be time-consuming it opens a line of communication with the package authors and the community, perhaps leading to a better enhancement or more effective fixes!
 
 Once there is consensus that a PR based on the issue would be helpful, adhering to the following process will make things proceed more quickly: