Fix webapp crash when no pipeline

[JosephMarinier]

Resolve #331

Description:

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[JosephMarinier]

This inappropriate ! was letting a null in, which was crashing PipelineSelect.

[christyler3030]

This looks good to me. Just want to confirm that this is the desired behaviour:
No pipelines -> don't render the selector
rather than
No pipelines -> render empty selector.

[JosephMarinier]

This looks good to me. Just want to confirm that this is the desired behaviour:
No pipelines -> don't render the selector
rather than
No pipelines -> render empty selector.

Good question @christyler3030. 👍 I wanted to do the quickest fix possible so JavaScript stops crashing and it was midnight so I didn't think too much. Let's take the time now, it's not so much of a rush.

I like your alternative suggestion. In fact, that's how it used to work before the bug was introduced here, so I'll revert to that. It has two (other) benefits:

1. The place for the select menu is taken while the config loads, as opposed to popping and moving the project name once it loads.
2. This implementation supports pipelines being [] the same as when it is null.

Suggested change

	pipelines={config.pipelines}
	pipelines={config?.pipelines ?? []}

On that topic, note that the back end currently crashes with an unclear error message when you configure "pipeline": []. I created an issue to look into this: #335