[vscode] 6/n update Route Table with env api

Summary:

Stack contains changes that updates overall environment setup flow for vscode extension.

This diff adds support to call "SET_ENV_FILE_PATH" implemented in the previous diff.

No functional changes.

Test Plan:

vscode-extension/src/util.ts

@@ -45,6 +45,8 @@ export const EDITOR_SERVER_ROUTE_TABLE = {
     urlJoin(hostUrl, EDITOR_SERVER_API_ENDPOINT, "/load_content"),
   LOAD_MODEL_PARSER_MODULE: (hostUrl: string) =>
     urlJoin(hostUrl, EDITOR_SERVER_API_ENDPOINT, "/load_model_parser_module"),
+  SET_ENV_FILE_PATH: (hostUrl: string) =>
+    urlJoin(hostUrl, EDITOR_SERVER_API_ENDPOINT, "/set_env_file_path"),
 };
 
 export async function isServerReady(serverUrl: string) {