Add repeatable-builds.sh and test Oswald as well #1916

Job	Run time
Build GS and check the result	3m 3s
Build GS and check the result	2m 51s
Build GS and check the result	2m 45s
cargo check no std	1m 31s
cargo check no std	1m 14s
cargo check no std	1m 19s
Rustfmt	45s
Rustfmt	40s
Rustfmt	40s
resources/scripts/ots_test.sh	55s
resources/scripts/ots_test.sh	56s
resources/scripts/ots_test.sh	55s
Clippy lints	57s
Clippy lints	1m 2s
Clippy lints	55s
cargo test fea-rs	54s
cargo test fea-rs	2m 18s
cargo test fea-rs	53s
fontbe tests	44s
fontbe tests	44s
fontbe tests	43s
fontc tests	1m 7s
fontc tests	1m 5s
fontc tests	56s
tests other than fontbe,fontc	1m 46s
tests other than fontbe,fontc	1m 49s
tests other than fontbe,fontc	1m 42s
	35m 9s

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