[wasm] esm integration test updates

[guybedford]

Implementation fixes and follow up on the previous test cases for the ESM Integration source phase imports that were added in #42467.

• Fixes the global test to not throw a TDZ error
• Fixes the negation test that WebAssembly.Module is not Object.prototype
• Fixes the sample Wasm to use the empty Wasm binary instead of another constructed binary
• Fixes the WebAssembly.Module.exports test to map the name field before asserting
• Adds the worker test entry point instead of treating it as inaccessible.
• Adds esm-integration script-src verification tests for both permitting and denying Wasm modules through CSP.