[browser][debugger] Clean up MessageId logic to prepare for sessions in the test harness (#43188)
* Clean up MessageId logic
* Update src/mono/wasm/debugger/DebuggerTestSuite/InspectorClient.cs
Co-authored-by: Ankit Jain <radical@gmail.com>
* Update src/mono/wasm/debugger/DebuggerTestSuite/InspectorClient.cs
Co-authored-by: Ankit Jain <radical@gmail.com>
* Update src/mono/wasm/debugger/DebuggerTestSuite/InspectorClient.cs
Co-authored-by: Ankit Jain <radical@gmail.com>
Co-authored-by: Ankit Jain <radical@gmail.com>