Update ReDoc version to 2.1.1 (#392) #999

Job	Run time
clippy	1m 4s
coverage	2m 39s
doc	1m 15s
readme	22s
rustfmt	19s
test-trybuild	2m 57s
Test on Rust MSRV with default features	5m 45s
Test on Rust MSRV with openapi features	5m 22s
Test on Rust MSRV with full features	5m 27s
Test on Rust Stable with default features	1m 47s
Test on Rust Stable with openapi features	1m 34s
Test on Rust Stable with full features	1m 48s
Test on Rust beta with default features	1m 38s
Test on Rust beta with openapi features	1m 38s
Test on Rust beta with full features	1m 59s
Test on Rust nightly with default features	1m 28s
Test on Rust nightly with openapi features	1m 28s
Test on Rust nightly with full features	1m 38s
webpack	13s
pages	10s
	40m 31s

Provide feedback