Deduplicate acorn import

[lukastaegert]

This PR contains:

• bugfix
• feature
• refactor
• documentation
• other

Are tests included?

• yes (bugfixes and features will not be merged without tests)
• no

Breaking Changes?

• yes (breaking changes will not be merged unless absolutely necessary)
• no

List any relevant issue numbers:

Description

When switching to latest rollup-plugin-node-resolve, we suddenly had two copies of acorn in the build as acorn does not use module in its export conditions. This fixes it, noticeably reducing file size again.

[rollup-bot]

Thank you for your contribution! ❤️

You can try out this pull request locally by installing Rollup via

npm install rollup/rollup#deduplicate-acorn

or load it into the REPL:
https://rollupjs.org/repl/?circleci=14003

[codecov]

Codecov Report

Merging #3929 (c8722e3) into master (f051067) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #3929   +/-   ##
=======================================
  Coverage   97.13%   97.13%           
=======================================
  Files         188      188           
  Lines        6669     6669           
  Branches     1940     1940           
=======================================
  Hits         6478     6478           
  Misses        101      101           
  Partials       90       90           

Impacted Files	Coverage Δ
src/utils/options/normalizeInputOptions.ts	100.00% <ø> (ø)

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