Update CONTRIBUTING.md

Fix typos

CONTRIBUTING.md

@@ -33,7 +33,7 @@ The `PR` should include following information:
 * A descriptive **title** on what changed.
 * A detailed **description** of changes.
 * If you made changes to the UI please add a **screenshot** or **video** as well.
-* If there is a related issue please add a **reference to the issue**. If not create one beforehand an link it.
+* If there is a related issue please add a **reference to the issue**. If not, create one beforehand and link it.
 * If your PR is still in progress mark it as **Draft**.
 
 ### Checks, Tests & Documentation
@@ -44,7 +44,7 @@ Note: If it is your first PR, an admin will need to request a review for you.
 
 > Please resolve all `Violation` errors in Xcode (except: _TODO:_ warnings). Otherwise the swiftlint check on GitHub will fail.
 
-Once you submitted the `PR` GitHub will run a couple of actions which run tests and `SwiftLint` (this can take a couple of minutes). Should a test fail it cannot be merged until tests succeed.
+Once you submit the `PR` GitHub will run a couple of actions which run tests and `SwiftLint` (this can take a couple of minutes). Should a test fail, it cannot be merged until tests succeed.
 
 Make sure to resolve all merge-conflicts otherwise the `PR` cannot be merged.