tests: add test for missing packages

[rishabh3112]

What kind of change does this PR introduce?
feature/ tests

Did you add tests for your changes?
yes

If relevant, did you update the documentation?
N/A

Summary
Currently we were not test missing package case, should increase coverage there

Does this PR introduce a breaking change?
No

Other information
No

[codecov]

Codecov Report

Merging #2296 (023fac2) into master (b6884fa) will not change coverage.
The diff coverage is 87.50%.

@@           Coverage Diff           @@
##           master    #2296   +/-   ##
=======================================
  Coverage   68.10%   68.10%           
=======================================
  Files          52       52           
  Lines        2060     2060           
  Branches      507      507           
=======================================
  Hits         1403     1403           
  Misses        657      657           

Impacted Files	Coverage Δ
packages/generators/addon-template/package.json.js	100.00% <ø> (ø)
packages/generators/init-template/package.json.js	100.00% <ø> (ø)
packages/generators/init-template/tsconfig.json.js	100.00% <ø> (ø)
packages/generators/src/types/index.ts	100.00% <ø> (ø)
packages/generators/src/init-generator.ts	90.00% <83.33%> (ø)
packages/configtest/src/index.ts	94.73% <100.00%> (ø)
packages/generators/src/addon-generator.ts	94.11% <100.00%> (ø)

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[alexander-akait]

@rishabh3112 Can you rebase?

[rishabh3112]

Sure, will do tomorrow.

[alexander-akait]

@rishabh3112 Can you rebase?

[rishabh3112]

Done @alexander-akait

[alexander-akait]

Good job!