Add missing addons/docs dependency for fs-extra

[acusti]

Issue: line 1 of addons/docs/src/preset.js is import fs from 'fs-extra';, but fs-extra is missing from addons/docs’ package.json.

What I did

i added "fs-extra": "^9.0.1", to the package.json dependencies (the same version string that i found elsewhere, e.g. in core-common)

How to test

i ran into this issue when trying to upgrade to storybook v7.0.0-alpha.37 in a codebase using the vite builder and yarn v3.2.4. the specific error is:

WARN   Failed to load preset: {"name":"/Users/me/my-repo/.yarn/__virtual__/@storybook-addon-docs-virtual-8d4a2f6481/0/cache/@storybook-addon-docs-npm-7.0.0-alpha.37-95b089e905-abc8952e75.zip/node_modules/@storybook/addon-docs/preset.js"} on level 3
ERR! Error: @storybook/addon-docs tried to access fs-extra, but it isn't declared in its dependencies; this makes the require call ambiguous and unsound.
ERR!
ERR! Required package: fs-extra
ERR! Required by: @storybook/addon-docs@virtual:62e895eaa74935c5722a4de41d4984328b771f05bc9888b3fd8210e5282d0c5555d799ab7a4041d2fcfa758b27814e74dbaddade60b7b0a4795629e4e3c125c0#npm:7.0.0-alpha.37 (via /Users/me/my-repo/.yarn/__virtual__/@storybook-addon-docs-virtual-8d4a2f6481/0/cache/@storybook-addon-docs-npm-7.0.0-alpha.37-95b089e905-abc8952e75.zip/node_modules/@storybook/addon-docs/dist/cjs/)

i worked around it by adding the dependency via packageExtensions in my .yarnrc.yml. this fix can be verified by checking to see that the error above no longer occurs when running storybook using the vite builder on yarn. but it’s also self-evidently correct, so there’s that.

note that i ran into the same kind of issue from @storybook/common-core requiring @storybook/react-vite even though it isn‘t in its deps, but i think that might be a dynamic require that comes from .storybook/main.js’s framework.name, so i’m not sure how that should be resolved.

[shilman]

Thanks @acusti !!! 🙏