* Reapply "Add "type" = "module" to ensure it is present (#4350)" (#4352)
This reverts commit 8214fd7156.
* Mark prettier config file as CommonJS
I *think* this will fix a problem with the release process in which we saw an
error:
```
Error: Invalid configuration for file "/home/runner/work/matrix-js-sdk/matrix-js-sdk/package.json":
Error: module is not defined in ES module scope
Error: This file is being treated as an ES module because it has a '.js' file extension and '/home/runner/work/matrix-js-sdk/matrix-js-sdk/package.json' contains "type": "module". To treat it as a CommonJS script, rename it to use the '.cjs' file extension.
```
