Fix NUL string error

[ericphanson]

#6 with a test added.

Closes #6

(I tried pushing a commit but it made a local branch instead, hence this separate PR)

[codecov]

Codecov Report

Merging #7 (77922cf) into main (23ce74b) will not change coverage.
The diff coverage is 100.00%.

@@            Coverage Diff            @@
##              main        #7   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files            1         2    +1     
  Lines            5        35   +30     
=========================================
+ Hits             5        35   +30     

Impacted Files	Coverage Δ
src/LicenseCheck.jl	100.00% <100.00%> (ø)
src/find_licenses.jl	100.00% <100.00%> (ø)

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[giordano]

I wanted to add also a test that makes sure license_table fails when validate_strings=false

[giordano]

But besides that, the test is perfect 🙂

[ericphanson]

Good call! Added