fix typo

Author: mark-i-m

src/tests/intro.md

@@ -211,7 +211,7 @@ caveats:
   that the crate doesn't compile any more (e.g. used old nightly features),
   has broken or flaky tests, requires network access, or other reasons.
 
-- Before crater can be run, `@bors try` needs to suceed in building artifacts.
+- Before crater can be run, `@bors try` needs to succeed in building artifacts.
   This means that if your code doesn't compile, you cannot run crater.
 
 ## Perf runs