Adding instructions on how to build Gradio-Lite locally (#6870)
* changes
* Fix scripts/launch_lite.sh removing the unnecessary execution of `python -m http.server`
* Add an exec permission to scripts/launch_lite.sh (`chmod +x`)
* Update launch_lite.sh to run the pybuild command when necessary
* Update CONTRIBUTING.md
* Fix scripts/build_lite.sh
* rename
* Update CONTRIBUTING.md
* Update scripts/run_lite.sh
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Co-authored-by: Yuichiro Tachibana (Tsuchiya) <t.yic.yt@gmail.com>
