[Doc]: Add more social networking links(dev-1.x)

[JoyMei]

Thanks for your contribution and we appreciate it a lot. The following instructions would make your pull request more healthy and more easily get feedback. If you do not understand some items, don't worry, just make the pull request and seek help from maintainers.

Motivation

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Modification

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BC-breaking (Optional)

Does the modification introduce changes that break the back-compatibility of the downstream repos?
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Use cases (Optional)

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Checklist

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2. The modification is covered by complete unit tests. If not, please add more unit test to ensure the correctness.
3. If the modification has potential influence on downstream projects, this PR should be tested with downstream projects.
4. The documentation has been modified accordingly, like docstring or example tutorials.

[CLAassistant]

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[OpenMMLab-Assistant-004]

Hi @JoyMei ！First of all, we want to express our gratitude for your significant PR in the mmdetection3d project. Your contribution is highly appreciated, and we are grateful for your efforts in helping improve this open-source project during your personal time. We believe that many developers will benefit from your PR.

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