test: fix help style test when FORCE_COLOR is in parent env

The NO_COLOR and alignment-preservation tests inherited FORCE_COLOR
from process.env, which takes precedence over NO_COLOR and caused
the tests to fail on CI environments where FORCE_COLOR is set.
Delete FORCE_COLOR from the child env in those test cases.

Signed-off-by: Adrian Estrada <edsadr@gmail.com>

Author: edsadr

test/parallel/test-cli-node-print-help-style.js

@@ -27,6 +27,7 @@ function stripAnsi(text) {
 // Test: NO_COLOR=1 produces plain output
 {
   const env = { ...process.env, NO_COLOR: '1' };
+  delete env.FORCE_COLOR;
   execFile(process.execPath, ['--help'], { env },
            common.mustSucceed((stdout) => {
              assert.ok(stripAnsi(stdout) === stdout,
@@ -51,6 +52,7 @@ function stripAnsi(text) {
 {
   const envStyled = { ...process.env, FORCE_COLOR: '1' };
   const envPlain = { ...process.env, NO_COLOR: '1' };
+  delete envPlain.FORCE_COLOR;
   execFile(process.execPath, ['--help'], { env: envStyled },
            common.mustSucceed((styledStdout) => {
              execFile(process.execPath, ['--help'], { env: envPlain },