chore: replace 'global' with 'globalThis'

[bradenmacdonald]

The global keyword is a non-standard NodeJS specific keyword. But since 2019, we can use globalThis instead, which works in every runtime. For example, globalThis has the same consistent meaning in both browsers and NodeJS, whereas global does not work in browsers unless you use some build process to rewrite it to window.

Details: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/globalThis#description

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Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 83.41%. Comparing base (9d2e727) to head (d331922).

Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #701 +/- ## ======================================= Coverage 83.41% 83.41% ======================================= Files 40 40 Lines 1073 1073 Branches 197 197 ======================================= Hits 895 895 Misses 166 166 Partials 12 12 ```

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