[Adaptive] Missing type declaration: botframework-expression

[boydc2014]

Versions

4.future 10/25

Describe the bug

Referring botbuilder-lg from another ts project don't work out-of-box.

node_modules/botframework-expressions/lib/commonRegex.d.ts:9:27 - error TS7016: Could not find a declaration file for module 'lru-cache'. 
'C:/Users/donglei/code/testg/node_modules/lru-cache/index.js' implicitly has an 'any' type.
  Try `npm install @types/lru-cache` if it exists or add a new declaration (.d.ts) file containing `declare module 'lru-cache';`

9 import * as LRUCache from 'lru-cache';

To Reproduce

Steps to reproduce the behavior:

1. create a new ts project
2. refer to botbuilder-lg
3. create an lg file and add code to evaluate it
4. tsc

Expected behavior

no errors

Additional context

I can add @types/lru-cache to make it work, but i should not manually added another package it don't use directly.

[bug]