chore: add browser testing infrastructure

[nedsalk]

Huge shoutout to @danielbate with whom I had multiple discussions and debugging sessions to get this working!

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The idea is to run an http server that has the responsibility of launching and killing fuel-core nodes and the functionality would be transparent to launchTestNode, meaning all the @group node tests that use launchTestNode can be reused for @group browser tests as well.

This is achieved by setting an environment variable based on which the internals of launchTestNode/setupTestProviderAndWallets either use launchNode (in node tests) or send requests to the http server (browser tests).

I'll write documentation for the utility once we dogfood this in our whole test suite and verify everything works as expected. We might also put it behind a fuels cli command, but I'd also rather do that when we want to make this generally available.

closes #284, #2178

[github-actions]

Coverage Report:

Lines	Branches	Functions	Statements
80.04%(-0.92%)	72.03%(-0.52%)	76.85%(-1.13%)	80.09%(-0.92%)

Changed Files:

Ok	File (✨=New File)	Lines	Branches	Functions	Statements
🔴	internal/check-tests/src/index.ts	80% (-10%)	66.66% (-22.22%)	100% (+0%)	81.81% (-9.09%)
🔴	packages/account/src/connectors/fuel.ts	91.03% (-5.52%)	89.33% (+0%)	80.95% (-14.28%)	90.72% (-5.96%)
🔴	packages/account/src/connectors/types/local-storage.ts	60% (-20%)	100% (+0%)	60% (-20%)	60% (-20%)
🔴	packages/account/src/connectors/utils/dispatch-fuel-connector-event.ts	0% (-100%)	100% (+0%)	0% (-100%)	0% (-100%)
🔴	packages/account/src/test-utils/launchNode.ts	100% (+0%)	86.44% (+0%)	77.77% (+0%)	94.95% (+0.04%)
🔴	packages/account/src/test-utils/setup-test-provider-and-wallets.ts	80% (-20%)	90% (-10%)	66.66% (-33.34%)	80% (-20%)
🔴	✨ packages/fuels/src/setup-launch-node-server.ts	0% (+0%)	0% (+0%)	0% (+0%)	0% (+0%)