ci: fix coverage taking into account js files

[bgatellier]

Changelog

Remove the following directories and files from coverage calculation:

• [x] lib/ directories (packages build output)
• [x] templates/ directory
• [x] packages/*/tests directory
• [x] __mocks__ directories

[changeset-bot[bot]]

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Latest commit: f4400e239ceb7a53629aa9bc8b7d768f89ca9bf7

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