Added CLA info to pull request template

.github/pull_request_template.md

@@ -5,3 +5,11 @@ Welcome to the 🐸STT project! We are excited to see your interest, and appreci
 This repository is governed by the Contributor Covenant Code of Conduct. For more details, see the [CODE_OF_CONDUCT.md](CODE_OF_CONDUCT.md) file.
 
 In order to make a good pull request, please see our [CONTRIBUTING.rst](CONTRIBUTING.rst) file, in particular make sure you have set-up and run the pre-commit hook to check your changes for code style violations.
+
+Before accepting your pull request, you will be asked to sign a [Contributor License Agreement](https://cla-assistant.io/coqui-ai/STT).
+
+This [Contributor License Agreement](https://cla-assistant.io/coqui-ai/STT):
+
+- Protects you, Coqui, and the users of the code.
+- Does not change your rights to use your contributions for any purpose.
+- Does not change the license of the 🐸STT project. It just makes the terms of your contribution clearer and lets us know you are OK to contribute.