Pipeline CLI: Add support for static text spinner

[ptitzler]

Improves the rendering of 'in progress' for long running tasks in the elyra-pipeline CLI, such as pipeline submission or pipeline monitoring.

Output when the CLI is running in a terminal window - note the animations:

$ elyra-pipeline submit test.pipeline --runtime-config kfp_test_env --monitor

Output when the CLI is running in a terminal window and the output is sent to a pipe - no animations:

$ elyra-pipeline submit test.pipeline --runtime-config kfp_test_env --monitor | cat

The main goal is to minimize the amount of information that is logged if the CLI is run non-interactively, e.g. in batch.

Example of captured STDOUT output prior to this PR:

$ elyra-pipeline submit test.pipeline --runtime-config kfp_test_env --monitor > a.out
$ cat a.out

Closes #2617

What changes were proposed in this pull request?

• Add/use a new 'in progress' spinner that displays only text, without any animation

How was this pull request tested?

See invocation examples above

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[elyra-bot]

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[kevin-bates]

Nice.

[ptitzler]

Confirmed that the CI output is now clean:

For comparison, this is what the output looked before: