feat: library definition for PlatformIO

[obones]

Many embedded projects are using PlatfomIO as a development environment, in particular in the ESP32 world.

It is possible to use third party libraries via such a definition in the project platform.io file:

lib_deps = 
    https://github.com/boblemaire/asyncHTTPrequest

For this to work, the referenced project must include a library.json file describing the library and its folder layout.

This PR provides the file so that flatbuffers is usable as a dependency in PlatformIO, as requested by #7189

[google-cla]

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[github-actions]

This pull request is stale because it has been open 6 months with no activity. Please comment or label not-stale, or this will be closed in 14 days.

[obones]

Hello
What can I do to "unstale" this branch?
I believe there needs to have an "approving review" but I'm not sure how to get this

[FlavioZanoni]

@obones the branch is stale because it hasn't had any commits for the past few months. Have you signed the CLA ?

[obones]

@obones the branch is stale because it hasn't had any commits for the past few months. Have you signed the CLA ?

I believe I did, at least that's what I inferred from the cla/google check being successful.

[FlavioZanoni]

I have created a PR to your branch to update the version in the library.json with the release. I think its just a matter of waiting for a maintainer

[obones]

Thanks, I have merged it and rebased my branch on top of master.
Hopefully someone will notice this PR.

[sylque]

So it seems this never got merged? Too bad...

[obones]

So it seems this never got merged? Too bad...

Well, I just rebased it once more, for any one to look at.
I sincerely have no idea why "buildifier" is not happy