Fix infura client chain ID

[rekmarks]

Our eth_chainId implementation in createInfuraClient.js declared its chain ID values inline, and they were incorrectly 0-padded. This PR fixes this by using the network enums for both net_version and eth_chainId.

[Gudahtt]

This is a breaking change. I'm not sure we should include this in v8 without any notice.

[metamaskbot]

Builds ready [caad6fc]

• builds: chrome, firefox, opera
• bundle viz: background, ui, inpage, contentscript, ui-libs, bg-libs, phishing-detect
• dep viz: background
• all artifacts

Page Load Metrics (622 ± 61 ms)

Platform	Page	Metric	Min (ms)	Max (ms)	Average (ms)	StandardDeviation (ms)	MarginOfError (ms)
Chrome	Home	firstPaint	31	106	44	17	8
		domContentLoaded	372	828	620	127	61
		load	374	830	622	127	61
		domInteractive	372	827	620	127	61

[rekmarks]

@Gudahtt yeah, I agree. We should discuss internally and circle back.

[brad-decker]

approval was based on code check, missed the comments about breaking changes.

We shouldn't merge this yet.

[rekmarks]

@brad-decker no worries, we'll hold off for now!

[danjm]

@rekmarks I'm guessing this PR can be closed?

[rekmarks]

@danjm this is part of the November 16 breaking changes.

[rekmarks]

Which I will now create a label for.

[metamaskbot]

Builds ready [ba36c2d]

• builds: chrome, firefox, opera
• bundle viz: background, ui, inpage, contentscript, ui-libs, bg-libs, phishing-detect
• dep viz: background
• all artifacts

Page Load Metrics (504 ± 50 ms)

Platform	Page	Metric	Min (ms)	Max (ms)	Average (ms)	StandardDeviation (ms)	MarginOfError (ms)
Chrome	Home	firstPaint	33	88	58	20	10
		domContentLoaded	307	692	502	103	50
		load	308	694	504	104	50
		domInteractive	306	692	501	103	50

[rekmarks]

@brad-decker this is ready for review!