Eliminate artificial delay in swaps loading screen after request loading is complete

[danjm]

Previous to this PR, we were adding an artificial delay to the length of time that each logo, name and fox look was shown on the swaps loading screen after the network request that is loading is complete. This was to give the user time to reading names and logos.

It has been decided that it is preferable to move the user to the view-quote screen faster then to give the user extra time to read names. The most important reason for this is that it will increase swaps success rates as the shorter the time between the retrieval of quotes and the submission of swaps, the more likely that the swap will be successful. There have been recent api improvements that reduce the average time for the /trades request to respond, which means that the changes added in this PR will have an affect much more often.

This is what the loading screen will look like when the /trades request takes only 2-3 seconds.

Peek.2021-02-23.10-47.mp4

[github-actions]

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[metamaskbot]

Builds ready [08b75e4]

• builds: chrome, firefox, opera
• bundle viz: background, ui, inpage, contentscript, ui-libs, bg-libs, phishing-detect
• build viz: Build System
• code coverage: Report
• storybook: Storybook
• all artifacts

Page Load Metrics (574 ± 15 ms)

Platform	Page	Metric	Min (ms)	Max (ms)	Average (ms)	StandardDeviation (ms)	MarginOfError (ms)
Chrome	Home	firstPaint	43	72	60	9	4
		domContentLoaded	521	670	572	31	15
		load	522	671	574	31	15
		domInteractive	520	669	572	31	15

[darkwing]

This feels much nicer; I'm glad we're moving forward on this!