docs: Include GNOME bash script for Dark Mode #3611

Job	Run time
License checks	1m 28s
Extract crate metadata	3s
Ensure 'cargo fmt' has been run	4s
cargo audit	8s
Documentation	36s
Run tests with system wide configuration	2m 18s
Run tests with updated syntaxes and themes	4m 39s
Minimum supported rust version	1m 23s
aarch64-unknown-linux-gnu (ubuntu-20.04)	3m 54s
arm-unknown-linux-gnueabihf (ubuntu-20.04)	3m 58s
arm-unknown-linux-musleabihf (ubuntu-20.04)	3m 56s
i686-pc-windows-msvc (windows-2019)	6m 44s
i686-unknown-linux-gnu (ubuntu-20.04)	3m 43s
i686-unknown-linux-musl (ubuntu-20.04)	3m 53s
x86_64-apple-darwin (macos-12)	5m 0s
x86_64-pc-windows-gnu (windows-2019)	7m 18s
x86_64-pc-windows-msvc (windows-2019)	6m 20s
x86_64-unknown-linux-gnu (ubuntu-20.04)	3m 44s
x86_64-unknown-linux-musl (ubuntu-20.04)	3m 50s
all-jobs	1s
Publish to Winget	0s
	1h 3m 0s

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