Common opt-out of telemetry environment variables

Common telemetry opt-out variables include:

- Universal: `DO_NOT_TRACK=1`
- .NET SDK: `DOTNET_CLI_TELEMETRY_OPTOUT=1`
- Next.js: `NEXT_TELEMETRY_DISABLED=1`
- Homebrew: `HOMEBREW_NO_ANALYTICS=1`
- Astro: `ASTRO_TELEMETRY_DISABLED=1`
- Gatsby: `GATSBY_TELEMETRY_DISABLED=1`
- PowerShell: `POWERSHELL_TELEMETRY_OPTOUT=1`
- GitHub CLI: `GH_NO_TELEMETRY=1`
- Storybook: `STORYBOOK_DISABLE_TELEMETRY=1`
- Prisma: `CHECKPOINT_DISABLE=1`