Fix minor typos in doc/quickstart
@@ -102,7 +102,7 @@ Unless there are errors, this won't print anything.
Because this command executes the provided test suite for every mutation
it selected, it will require many times more time to execute than the
whole test suite. It can be killed at any point though and restarted
- while keepting the status of executated mutations between the runs.
+ while keeping the status of executed mutations between the runs.
View the results
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