[Record and Playback] Skip functionality in common recorder

[HarshaNalluru]

Skip list to skip a test -

const skip = [	
  // Abort	
  "browsers/aborter/recording_should_abort_after_aborter_timeout.json"	
];

Managing the list of test names would mean that we should frequently update them whenever a test name changes or a new test is added.
The plan is to avoid the skip list becoming stale in the following way.

This PR attempts to provide a .skip() method with the recorder from @azure/test-utils-recorder that can be called from the it block to skip a test.

Let us take a moment to understand what happens with this change.

• We no longer need to save/update the skip list
• Test can be skipped by calling recorder.skip("browser"); or recorder.skip("node"); in the it block based on the environment we want the test to be skipped
• In the record mode, the recording will be generated with the info right from when the recorder is invoked in beforeeach until the skip() method that is invoked in the it block.
  • We need to save(and commit) this recording for the playback mode since the recorder has no way to know that the test is being skipped until the skip() method is called.
    [ A small tradeoff for getting rid of skip list and still add the convenience of invoking the recorder in beforeeach ]

Reference - #4336

[sadasant]

Follow the feedback and land this! 🌞