remove redundant check

Author: guybedford

lib/internal/repl/await.js

@@ -110,11 +110,9 @@ function processTopLevelAwait(src) {
     // Convert keyword parse errors on await into their original errors when
     // possible.
     if (errPos === awaitPos + 6 &&
-        src.slice(errPos - 6, errPos - 1) === 'await' &&
         e.message.includes('Expecting Unicode escape sequence'))
       return null;
     if (errPos === awaitPos + 7 &&
-        src.slice(errPos - 7, errPos - 2) === 'await' &&
         e.message.includes('Unexpected token'))
       return null;
     const { line, column } = e.loc;