test: fix ts compiler error

Author: jbedard

tests/legacy-cli/e2e/utils/process.ts

@@ -109,8 +109,8 @@ function _exec(options: ExecOptions, cmd: string, args: string[]): Promise<Proce
       );
     });
     childProcess.on('error', (error) => {
-      err.message += `${error}...\n\nSTDOUT:\n${stdout}\n\nSTDERR:\n${stderr}\n`;
-      reject(err);
+      error.message += `${error}...\n\nSTDOUT:\n${stdout}\n\nSTDERR:\n${stderr}\n`;
+      reject(error);
     });
 
     if (options.waitForMatch) {