RepoSync with changes to `commitMutation` and updates to product code to remove explicit type annotations and use typed `graphql` tags for mutations.

[alunyov]

Summary: This is a RepoSync diff with changes to the product code:

• Main change here is the updated commitMutation types that are using typed graphql tags.
• Also this diff contains changes (mostly automated) to the product code that removes the explicit type annotations. See details on the codemod here: https://www.internalfb.com/intern/wiki/Relay-team/Flow_Integration/
• Additionally, this diff contain new $FlowFixMe in the places where new types uncovered issues with types.

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Individual diffs for review: Product code changes: D48563977 FlowFixMe: D48563978

Reviewed By: captbaritone

Differential Revision: D48543114

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This pull request was exported from Phabricator. Differential Revision: D48543114

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This pull request was exported from Phabricator. Differential Revision: D48543114

[facebook-github-bot]

This pull request was exported from Phabricator. Differential Revision: D48543114

[facebook-github-bot]

This pull request was exported from Phabricator. Differential Revision: D48543114