Add stderr to error message when pijul CLI command fails

Dependencies

• [2] ZGMIJNFV Create pijul.ts for executing commands using the Pijul CLI
• [3] IBRKAWNM Moved utility modules into their own folder
• [4] YUVLBWV3 Populate resource groups for unrecorded and untracked changes

Change contents

• replacement in src/pijul.ts at line 92
  [2.3008]→[2.3008:3113](∅→∅)
  − return await Promise.reject<IExecutionResult<string>>(new Error('Error executing pijul command'));
  [2.3008]

  [2.3113]
  + return await Promise.reject<IExecutionResult<string>>(new Error('Error executing pijul command: "' + bufferResult.stderr + '"'));