Remove `set_unconditionally` & `BeValue` #2911

Job	Run time
Rustfmt	1m 9s
resources/scripts/ots_test.sh	1m 9s
Build GS and check the result	2m 56s
cargo check no std	1m 37s
Clippy lints	1m 34s
cargo test fea-rs	1m 3s
fontc tests	1m 10s
fontbe tests	1m 0s
tests other than fontbe,fontc	2m 15s
	13m 53s

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