fix: support ES module syntax

[alexander-akait]

This PR contains a:

• bugfix
• new feature
• code refactor
• test update
• typo fix
• metadata update

Motivation / Use-Case

fix es module syntax

Breaking Changes

No

Additional Info

No

[codecov]

Codecov Report

Merging #435 into master will not change coverage.
The diff coverage is 100%.

@@          Coverage Diff          @@
##           master   #435   +/-   ##
=====================================
  Coverage     100%   100%           
=====================================
  Files           3      3           
  Lines         200    200           
  Branches       73     72    -1     
=====================================
  Hits          200    200

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

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