Fix license details

[nfriedly]

We updated to the latest release of the flatbuffers javascript library from npm, and Arnica threw up a warning that flatbuffers was using a non-standard license. However you're actually using a completely standard Apache 2.0 license, it was just mislabeled. (I diffed it against https://www.apache.org/licenses/LICENSE-2.0.txt to be sure and noticed that it didn't even have the copyright info filled in!)

So, this PR fixes two things:

1. package.json now uses the correct SPDX license identifier.
   • This is useful for automated tools that scan for license requirements, and will also allow https://www.npmjs.com/package/flatbuffers to show the correct license info.
   • See https://docs.npmjs.com/cli/v10/configuring-npm/package-json#license for more info
2. The copyright year and owner in the LICENSE file is now filled in
   • See https://www.apache.org/licenses/LICENSE-2.0.html#apply
   • Now removed from this PR

Feel free to edit that as appropriate. I can also split this into two PRs if preferred.

[google-cla[bot]]

Thanks for your pull request! It looks like this may be your first contribution to a Google open source project. Before we can look at your pull request, you'll need to sign a Contributor License Agreement (CLA).

View this failed invocation of the CLA check for more information.

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[nfriedly]

I am now a member of FullStory's corporate CLA group, but I'm not sure how to refresh the check here to recognize that. Nevermind, found the link at the bottom of of the cla check failure message.

[p0fi]

Could this pull request be merged? We are experiencing a similar issue with our license scan, which is complaining about the license not being allowed, even though it is actually completely allowed.

[dbaileychess]

Fixed: #8253