GH-3289: Introduce Parquet E2E test harness to support CLI testing

[ArnavBalyan]

• Currently parquet does not have a good mechanism to have e2e testing for CLI
• Developers have to manually call methods on the concrete class instead of the actual CLI route, this makes testing hard and prone to errors. Further the method return is tested instead of the actual console output.

• This change introduces a test harness which is a wrapper over main CLI class and provides utilities to implement CLI tests easily.
• Users can simply test with single line of code such as: cli("command").ok().matchOutputFromFile("txt"). The harness provides some other utilities like linecount, partial match etc.
• The CLI output can be added to a txt to ensure readability and test the actual console output

[ArnavBalyan]

cc @gszadovszky as followup thanks!

[gszadovszky]

Thank you @ArnavBalyan for picking this up. It is a great improvement to improve the test coverage of the cli!

[ArnavBalyan]

cc @gszadovszky this is ready thanks!

[gszadovszky]

@ArnavBalyan, could you check the failures?

[gszadovszky]

Thanks, @ArnavBalyan.

[gszadovszky]

Oh, the tests are still failing...

[ArnavBalyan]

Strangely I am not seeing it locally let me fix it

[Fokko]

@ArnavBalyan Gentle ping! Did you find some time to fix the test?

[ArnavBalyan]

Hi @Fokko thanks for the ping, I'll revive it in the coming week, looks like it was a formatting issue. Will try to fix soon!