docs: fix typo in CONTRIBUTING

Author: mtrezza

CONTRIBUTING.md

@@ -456,15 +456,15 @@ If the commit reverts a previous commit, use the prefix `revert:`, followed by t
 
 #### Local Testing
 
-Fixes for securify vulnerabilities are developed in private forks with a closed audience, inaccessible to the public. A current GitHub limitation does not allow to run CI tests on pull requests in private forks. Whether a pull requests fully passes all CI tests can only be determined by publishing the fix as a pull request and running the CI. This means the fix and implicitly information about the vulnerabilty are made accessible to the public. This increases the risk that a vulnerability fix is published, but then cannot be merged immediately due to a CI issue. To mitigate that risk, before publishing a vulnerability fix, the following tests needs to be run locally and pass:
+Fixes for securify vulnerabilities are developed in private forks with a closed audience, inaccessible to the public. A current GitHub limitation does not allow to run CI tests on pull requests in private forks. Whether a pull requests fully passes all CI tests can only be determined by publishing the fix as a public pull request and running the CI. This means the fix and implicitly information about the vulnerabilty are made accessible to the public. This increases the risk that a vulnerability fix is published, but then cannot be merged immediately due to a CI issue. To mitigate that risk, before publishing a vulnerability fix, the following tests needs to be run locally and pass:
 
 - `npm run test` (MongoDB)
 - `npm run test` (Postgres)
 - `npm run madge:circular` (circular dependencies)
 - `npm run lint` (Lint)
 - `npm run definitions` (Parse Server options definitions)
 
-### Merging
+#### Merging
 
 A current GitHub limitation does not allow to customize the commit message when merging pull requests of a private fork that was created to fix a security vulnerabilty. Our release automation framework demands a specific commit message syntax which therefore cannot be met. This prohibits to follow the process that GitHub suggest, which is to merge a pull request from a private fork directly to a public branch. Instead, after [local testing](#local-testing), a public pull request needs to be created with the code fix copied over from the private pull request.