fix(packages/typescript): Fix not to overwrite tsconfig

[sawa-zen]

Types of changes

• Bug fix (a non-breaking change which fixes an issue)
• New feature (a non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Description

The packages/typescript setup process is breaking the existing tsconfig.
For example, there is the following destruction.

{
  ...
  "compilerOptions": {
    "lib": [
      "dom",
      "es2015"
    ]
  },
  ...
}
↓
{
  "compilerOptions": {
    "lib": [
      "dom",
      "es2015",
      "dom"
    ]
  },
}

This is a problem due to using loash.defaultsDeep.
lodash/lodash#2801

But, I thought that overriding the default tsconfig settings to the existing tsconfig was a problem. So I changed to create a default tsconfig only when tsconfig did not exist.

Fixes: #5338

Checklist:

• My change requires a change to the documentation.
• I have updated the documentation accordingly. (PR: #)
• I have added tests to cover my changes (if not applicable, please state why)
• All new and existing tests are passing.

[codecov-io]

Codecov Report

Merging #5356 into dev will decrease coverage by <.01%.
The diff coverage is 33.33%.

@@           Coverage Diff           @@
##            dev   #5356      +/-   ##
=======================================
- Coverage    96%     96%   -0.01%     
=======================================
  Files        74      74              
  Lines      2529    2528       -1     
  Branches    640     641       +1     
=======================================
- Hits       2428    2427       -1     
  Misses       85      85              
  Partials     16      16

Impacted Files	Coverage Δ
packages/cli/src/utils/typescript.js	27.27% <0%> (-3.5%)	⬇️
packages/typescript/src/index.js	88.88% <66.66%> (-11.12%)	⬇️

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[kevinmarrec]

@sawa-zen Thanks for your time, we already planned to change this behavior, we will switch back to the extends way. So there won't be defaultDeeps anymore.

[danielroe]

This should also fix deploying Nuxt 2.5.x with TypeScript on Now, which currently produces the following fatal error:

FATAL  EACCES: permission denied, open '/home/nowuser/src/tsconfig.json'

[pi0]

Merged in #5367