fix(unzip): warn Windows 7 users of the unzip dependency

[malept]

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• The changes are appropriately documented (if applicable).
• The changes have sufficient test coverage (if applicable).
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Summarize your changes:

Addresses #1029.

[russlamb]

warning is showing on build

[codecov]

Codecov Report

Merging #1030 into master will not change coverage.
The diff coverage is 100%.

@@          Coverage Diff           @@
##           master   #1030   +/-   ##
======================================
  Coverage     100%    100%           
======================================
  Files          13      14    +1     
  Lines         677     687   +10     
======================================
+ Hits          677     687   +10

Impacted Files	Coverage Δ
src/unzip.js	100% <100%> (ø)
src/index.js	100% <100%> (ø)	⬆️

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