docs: updates labeling doc with lowercase labels; updates templates, readme

[Golodhros]

Summary of Changes

Updates docs and templates

Documentation

Labelling doc

CheckList

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• [x] PR title addresses the issue accurately and concisely. Example: "Updates the version of Flask to v1.0.2"
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• [x] PR includes a summary of changes.
• [x] PR adds unit tests, updates existing unit tests, OR documents why no test additions or modifications are needed.
• [x] In case of new functionality, my PR adds documentation that describes how to use it.
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