Add maxWarnings option to eslint

[mikew]

Closes #68

[mikew]

Have to use = here, as eslint --max-warnings -1 fails because it tries to parse -1 as a flag.

[fi3ework]

Thanks for your PR! I'll take a closer look over the weekend ASAP.

[codecov-commenter]

Codecov Report

Merging #69 (14bebd1) into main (df4917e) will decrease coverage by 0.11%.
The diff coverage is 0.00%.

@@            Coverage Diff             @@
##             main      #69      +/-   ##
==========================================
- Coverage   34.52%   34.40%   -0.12%     
==========================================
  Files          13       13              
  Lines         588      590       +2     
  Branches      114      115       +1     
==========================================
  Hits          203      203              
- Misses        384      386       +2     
  Partials        1        1              

Impacted Files	Coverage Δ
...es/vite-plugin-checker/src/checkers/eslint/main.ts	0.00% <0.00%> (ø)
packages/vite-plugin-checker/src/types.ts	100.00% <ø> (ø)

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update df4917e...14bebd1. Read the comment docs.

[fi3ework]

@mikew Thanks for your PR! Sorry to be so late in responding. I'll add some test cases and refactor some code then release a new version. Thanks!