Account for a custom nonce of zero

[tmashuang]

Fixes #8882

Seems that 0 isn't valid in || logic operator.

[metamaskbot]

Builds ready [6429004]

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

Page Load Metrics (1296 ± 74 ms)

Platform	Page	Metric	Min (ms)	Max (ms)	Average (ms)	StandardDeviation (ms)	MarginOfError (ms)
Chrome	Home	firstPaint	NaN	NaN	NaN	NaN	NaN
		domContentLoaded	1116	1654	1293	153	74
		load	1117	1657	1296	153	74
		domInteractive	1116	1654	1293	153	74

[Gudahtt]

We still use falsey checks on customNonceValue in a number of places, e.g. in confirm-transaction-base.container.js, which might be the only place this gets set in txMeta in practice? 🤔 So it still seems like this shouldn't work, unless I'm missing something.

[tmashuang]

I think in those instances it is set to a string.

Edit: I don't see where those instances where we type check customNonceValue .

[Gudahtt]

Ah I see - makes sense. I'll take another look.

[Gudahtt]

LGTM!