Update fetch-mock lib

[denis-rossati]

Summary

This PR will update the fetch-mock library from ^9 to ^12, adpating the code to the new mock interface.

Also, the test environment was changed to "jest-fixed-jsdom" since it patches the implementations of Request, Response and Headers globals, which are lacking in "jsdom" since it expect us to add polyfills for those globals.

Related issues

• Closes Bump node-fetch dependency on SDK #487

Checklist

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules
• I have checked my code and corrected any misspellings

[pkg-pr-new]

Open in StackBlitz

npm i https://pkg.pr.new/@croct/sdk@488

commit: 8239b75