Multiple config template attribute defaults can cause race condition

[donaldoakes]

Due to flowbee's update() calls triggering simultaneous document updates. For example if link.yaml has default values for both shape and points, the following stack is produced (unless action prop suppresses default update call).

 ERR Error: file:///Users/donald/workspaces/scorch/scorch/test/api/flows/flowbee.flow has changed in the meantime
    at i.apply (workbench.desktop.main.js:sourcemap:893:20315)
    at processTicksAndRejections (node:internal/process/task_queues:96:5)
    at async u._performTextEdits (workbench.desktop.main.js:sourcemap:2666:96787)
    at async u.perform (workbench.desktop.main.js:sourcemap:2666:96208)
    at async apply (workbench.desktop.main.js:sourcemap:2666:98420)
workbench.desktop.main.js:sourcemap:610  WARN IGNORING workspace edit Error: file:///Users/donald/workspaces/scorch/scorch/test/api/flows/flowbee.flow has changed in the meantime
    at i.apply (workbench.desktop.main.js:sourcemap:893:20315)
    at processTicksAndRejections (node:internal/process/task_queues:96:5)
    at async u._performTextEdits (workbench.desktop.main.js:sourcemap:2666:96787)
    at async u.perform (workbench.desktop.main.js:sourcemap:2666:96208)
    at async apply (workbench.desktop.main.js:sourcemap:2666:98420)