test: update test-stdout-to-file
Checklist
- [x ]
make -j8 test
(UNIX), orvcbuild test nosign
(Windows) passes - [x ] commit message follows commit guidelines
Affected core subsystem(s)
test
Description of change
- changed vars to const
- changed assert.equal to assert.strictEqual
- added a common.mustCall in the childProcess.exec callback
- replaced 2 console.log strings with template strings for readability
- broke up line 9 as it was causing a line max length (80) listing err