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## Current Behavior
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when running a generator, it does not check for the existence of a
prettier.config.mjs or .prettierrc.mjs file
## Expected Behavior
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When using a generator, it check for the existence of all config file
names specified in the docs.
## Related Issue(s)
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merged. -->
Fixes https://github.com/nrwl/nx/issues/21795
adds .mjs file names to checks
88ac601798