test: improve code in test-fs-open.js
Checklist
-
make -j4 test
(UNIX), orvcbuild test nosign
(Windows) passes -
tests and/or benchmarks are included -
commit message follows commit guidelines
Affected core subsystem(s)
test
Description of change
- use const instead of var for required modules
- use assert.strictEqual instead of assert.equal
- use assert.strictEqual instead of assert.ok
- use assert.ifError