Minor build fixes (#4317)

* always build app exp because storage and database will need it

* transform imports from @firebase/app-exp to @firebase/app

Author: Feiyang1

.github/workflows/test-changed.yml

@@ -28,6 +28,6 @@ jobs:
         cp config/ci.config.json config/project.json
         yarn
     - name: build
-      run: yarn build:changed core
+      run: yarn build:changed core --buildAppExp
     - name: Run tests on changed packages
       run: xvfb-run yarn test:changed core

packages/database/rollup.config.exp.js

@@ -19,6 +19,7 @@ import json from '@rollup/plugin-json';
 import typescriptPlugin from 'rollup-plugin-typescript2';
 import typescript from 'typescript';
 import path from 'path';
+import { importPathTransformer } from '../../scripts/exp/ts-transform-import-path';
 
 import pkg from './exp/package.json';
 
@@ -31,7 +32,8 @@ const deps = Object.keys(
  */
 const es5BuildPlugins = [
   typescriptPlugin({
-    typescript
+    typescript,
+    transformers: [importPathTransformer]
   }),
   json()
 ];
@@ -71,7 +73,8 @@ const es2017BuildPlugins = [
       compilerOptions: {
         target: 'es2017'
       }
-    }
+    },
+    transformers: [importPathTransformer]
   }),
   json({ preferConst: true })
 ];