[DataGrid] Fix onPageChange firing too often

[dtassone]

Fix #816, onPageChange firing multiple times

[oliviertassinari]

@dtassone Regarding the format of the pull request, I would recommend the following:

• We link the issue in the PR description so:
  1. the issue is closed automatically once this PR is merged: https://docs.github.com/en/free-pro-team@latest/github/managing-your-work-on-github/linking-a-pull-request-to-an-issue#linking-a-pull-request-to-an-issue-using-a-keyword
  2. the PR is referenced in the issue, right now, there is nothing:

• We polish the title of the pull request to be usable in the changelog, maybe something like this:
  [DataGrid] Fix onPageChange firing too often

[oliviertassinari]

I have commented on my understanding of how it should behave. The mental model I have always seen for the change event is: "does something try to change the current state?". For instance, when doing server-side rendering, the default page is already 1, I don't see why it should fire.