test: fix typo in gtest-all.cc

separater -> separator

PR-URL: #38224
Reviewed-By: Rich Trott <[email protected]>
Reviewed-By: Michaël Zasso <[email protected]>
Reviewed-By: Antoine du Hamel <[email protected]>

Author: eltociear

Diff for: test/cctest/gtest/gtest-all.cc

@@ -1995,7 +1995,7 @@ bool UnitTestOptions::MatchesFilter(
       return false;
     }
 
-    // Skips the pattern separater (the ':' character).
+    // Skips the pattern separator (the ':' character).
     cur_pattern++;
   }
 }