Move some of the dev dependencies to the top level

[fcollonval]

Fixes #112

[github-actions[bot]]

:point_left: Launch a binder notebook on the branch mamba-org/gator/fcollonval/issue112

[coveralls]

Pull Request Test Coverage Report for Build 388789937

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 67.983%

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Totals
Change from base Build 388773498:	0.0%
Covered Lines:	745
Relevant Lines:	1002

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💛 - Coveralls

[jtpio]

Thanks @fcollonval!

Do you think it would also make sense to move the eslint and prettier scripts to the top-level?

For example:

https://github.com/mamba-org/gator/blob/0ad6ce7f9a73577bb9503ba64e59e12271e5952c/packages/labextension/package.json#L35-L36

[fcollonval]

Do you think it would also make sense to move the eslint and prettier scripts to the top-level?

Sure, maybe specifying packages as the folder argument