Make sure generated code works in browser for RLC and Modular

[MaryGao]

Recently we recieved customer's issue for browser usage, but we haven't enabled browser testing for generated code yet. It's better to have that no matter unbranded or azure clients in both Modular and RLC.

In autorest we have the browser testing for HLC and RLC and see code here.

autorest.typescript/packages/autorest.typescript/package.json

Lines 14 to 17 in 78c804e

	"test:node": "npm run unit-test && npm run start-test-server:v2 & npm run integration-test:alone & npm run rlc-integration-test:alone & npm run test-version-tolerance & npm run stop-test-server",
	"test:node:alone": "npm run unit-test && npm run integration-test:alone && npm run rlc-integration-test:alone && npm run test-version-tolerance",
	"test:browser": "npm run start-test-server:v2 & npm run integration-test:browser & npm run rlc-integration-test:browser & npm run test-version-tolerance & npm run stop-test-server",
	"test:browser:alone": "npm run integration-test:browser && npm run rlc-integration-test:browser && npm run test-version-tolerance",

We could have similar steps to enable the brower testing for cadl-ranch cases. Considering we have browser coverage for azure-rlc so I think this is nice to have features but for other cases there exist testing gaps so they are must. But enabling all testing may be time-consuming we need to decide if we could select possible cases included.

autorest.typescript/packages/typespec-ts/package.json

Lines 54 to 57 in 78c804e

	"integration-test:alone:rlc": "cross-env TS_NODE_PROJECT=tsconfig.integration.json mocha -r ts-node/register --experimental-specifier-resolution=node --timeout 36000 ./test/integration/*.spec.ts",
	"integration-test:alone:azure-rlc": "cross-env TS_NODE_PROJECT=tsconfig.integration.json mocha -r ts-node/register --experimental-specifier-resolution=node --timeout 36000 ./test/azureIntegration/*.spec.ts",
	"integration-test:alone:modular": "cross-env TS_NODE_PROJECT=tsconfig.integration.json mocha -r ts-node/register --experimental-specifier-resolution=node --timeout 36000 ./test/modularIntegration/*.spec.ts",
	"integration-test:alone:azure-modular": "cross-env TS_NODE_PROJECT=tsconfig.integration.json mocha -r ts-node/register --experimental-specifier-resolution=node --timeout 36000 ./test/azureModularIntegration/*.spec.ts",

• testing for azure-rlc(nice to have)
• testing for unbranded-rlc(must to have)
• testing for azure-modular(must to have)
• testing for unbranded-modular(must to have)

[qiaozha]

Enable the whole spector tests on the browser environment would be too much and I feel like it will probably impact the ci efficiency? Maybe we could just select a few typical spector test cases here?