[docs] Fix description according to markdownlint (#2865)

README.md

@@ -32,17 +32,16 @@ Our primary documentation is at https://lightgbm.readthedocs.io/ and is generate
 
 Next you may want to read:
 
-* [**Examples**](https://github.com/microsoft/LightGBM/tree/master/examples) showing command line usage of common tasks.
-* [**Features**](https://github.com/microsoft/LightGBM/blob/master/docs/Features.rst) and algorithms supported by LightGBM.
-* [**Parameters**](https://github.com/microsoft/LightGBM/blob/master/docs/Parameters.rst) is an exhaustive list of customization you can make.
-* [**Parallel Learning**](https://github.com/microsoft/LightGBM/blob/master/docs/Parallel-Learning-Guide.rst) and [**GPU Learning**](https://github.com/microsoft/LightGBM/blob/master/docs/GPU-Tutorial.rst) can speed up computation.
-* [**Laurae++ interactive documentation**](https://sites.google.com/view/lauraepp/parameters) is a detailed guide for hyperparameters.
+- [**Examples**](https://github.com/microsoft/LightGBM/tree/master/examples) showing command line usage of common tasks.
+- [**Features**](https://github.com/microsoft/LightGBM/blob/master/docs/Features.rst) and algorithms supported by LightGBM.
+- [**Parameters**](https://github.com/microsoft/LightGBM/blob/master/docs/Parameters.rst) is an exhaustive list of customization you can make.
+- [**Parallel Learning**](https://github.com/microsoft/LightGBM/blob/master/docs/Parallel-Learning-Guide.rst) and [**GPU Learning**](https://github.com/microsoft/LightGBM/blob/master/docs/GPU-Tutorial.rst) can speed up computation.
+- [**Laurae++ interactive documentation**](https://sites.google.com/view/lauraepp/parameters) is a detailed guide for hyperparameters.
 
 Documentation for contributors:
 
-* [**How we update readthedocs.io**](https://github.com/microsoft/LightGBM/blob/master/docs/README.rst).
-* Check out the [**Development Guide**](https://github.com/microsoft/LightGBM/blob/master/docs/Development-Guide.rst).
-
+- [**How we update readthedocs.io**](https://github.com/microsoft/LightGBM/blob/master/docs/README.rst).
+- Check out the [**Development Guide**](https://github.com/microsoft/LightGBM/blob/master/docs/Development-Guide.rst).
 
 News
 ----
@@ -85,18 +84,17 @@ Ruby gem: https://github.com/ankane/lightgbm
 Support
 -------
 
-* Ask a question [on Stack Overflow with the `lightgbm` tag](https://stackoverflow.com/questions/ask?tags=lightgbm), we monitor this for new questions.
-* Discuss on the [LightGBM Gitter](https://gitter.im/Microsoft/LightGBM).
-* Discuss on the [LightGBM Slack team](https://lightgbm.slack.com).
-  * Use [this invite link](https://lightgbm-slack-autojoin.herokuapp.com/) to join the team.
-* Open **bug reports** and **feature requests** (not questions) on [GitHub issues](https://github.com/microsoft/LightGBM/issues).
+- Ask a question [on Stack Overflow with the `lightgbm` tag](https://stackoverflow.com/questions/ask?tags=lightgbm), we monitor this for new questions.
+- Discuss on the [LightGBM Gitter](https://gitter.im/Microsoft/LightGBM).
+- Discuss on the [LightGBM Slack team](https://lightgbm.slack.com).
+  - Use [this invite link](https://lightgbm-slack-autojoin.herokuapp.com/) to join the team.
+- Open **bug reports** and **feature requests** (not questions) on [GitHub issues](https://github.com/microsoft/LightGBM/issues).
 
 How to Contribute
 -----------------
 
 Check [CONTRIBUTING](https://github.com/microsoft/LightGBM/blob/master/CONTRIBUTING.md) page.
 
-
 Microsoft Open Source Code of Conduct
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