Explain usage of `<T: Config>` in FRAME storage + Update parachain pa… #7

Job	Run time
check-dependency-rules	12s
check-markdown	15s
check-workspace	18s
set-image	9s
check-toml-format	54s
check-rust-feature-propagation	1m 55s
check-umbrella	2m 6s
fmt	1m 12s
test-rust-features	1m 56s
	8m 57s

Provide feedback