Sourcemaps point to incorrect files

[isuru88]

After upgrading from 2.11.0 to 2.12.1, It seems like the packaged output does not contain src which is required by the source maps.

When using @apollo/client v3.3.11, webpack throws the following warning,

WARNING in C:/git/CustomizableSolution/node_modules/@apollo/client/node_modules/graphql-tag/lib/index.js
Module Warning (from C:/git/CustomizableSolution/node_modules/source-map-loader/index.js):
(Emitted value instead of an instance of Error) Cannot find source file '../src/index.ts': Error: Can't resolve '../src/index.ts' in 'C:\git\CustomizableSolution\node_modules\@apollo\client\node_modules\graphql-tag\lib'
 @ C:/git/CustomizableSolution/node_modules/@apollo/client/core/index.js 15:0-30 16:25-28 17:30-33 18:42-45 19:43-46 20:0-15
 @ C:/git/CustomizableSolution/node_modules/@apollo/client/index.js
 @ ./src/apolloClient.ts
 @ ./src/index.tsx
 @ multi C:/git/CustomizableSolution/node_modules/piral-cli-webpack/lib/set-path ./src/index.tsx

Steps to reproduce:

• Package using npm pack
• Extract and examine contents of .map type files within lib

Expected output:

• Since the sources point to files within src. package should contain src

Actual output:

• Package does not contain src

[ghost]

I have the exact same issue.

[prcdpr]

Same, can we get this PR merged?