The mangle reserved option does not stop labels from being renamed

[dasa]

Bug report

I'd like the output code to support this use case: https://esbuild.github.io/api/#drop-labels

I'd also like to not set compress to false, but I didn't find another way to keep Terser from removing the label. Related Issue: #1266

Version (complete output of terser -V or specific git commit)

REPL, but I think it's 5.22.0

Complete CLI command or minify() options used

REPL config:

{
  module: true,
  compress: false,
  mangle: { reserved: ["DEV", "example"] },
  output: {},
  parse: {},
  rename: {},
}

terser input

function example() {
  DEV: doAnExpensiveCheck()
  return normalCodePath()
}

terser output

function example(){n:doAnExpensiveCheck();return normalCodePath()}

Expected result

function example(){DEV:doAnExpensiveCheck();return normalCodePath()}

[fabiosantoscode]

This seems entirely reasonable. I don't have the time to work on all issues these days (there are so many!) but I'll gladly accept a PR for this.

The logic that needs to be updated is right here