add cache keygen to service action

[0x0a0d]

allow define keygen in action.cache that override cacher.defaultKeygen and cacher.keygen
use case

const serviceSchema = {
  actions: {
    find: {
      cache: {
        keygen(actionName, params, meta, defaultKeys) {
          // add meta.user._id to defaultKeys
          return this.defaultKeygen(actionName, params, meta, ['#user._id'].concat(defaultKeys))
        }
      }
    }
  }
}

[icebob]

Something is broken in CI test on Node 16. Could you check it?

[0x0a0d]

maybe it was a NodeJS bug (v16.9.0), use v16.8.0 will success

[icebob]

Thanks. I'm checking what is this.

[0x0a0d]

fixed in v16.9.1
https://github.com/nodejs/node/releases/tag/v16.9.1